XCOM 2 Class Analysis: SPARK
Like the Psi Operative, I'm only going to do one post on the SPARK. War of the Chosen does have a fairly notable impact on the SPARK, but the majority of it is indirect; they don't benefit from the switch from the Advanced Warfare Center to the Training Center, they inexplicably can't form Bonds, they ignore the Fatigue mechanic, and they can't be sent on Covert Operations. The overall net result being that SPARKs are notably less powerful relative to other classes in War of the Chosen, with the primary upside being that they can be sent on several missions back-to-back without tiring out. Notably, this means if you get a SPARK out early in War of the Chosen it might actually end up being your strongest for a portion of the midgame by virtue of hitting max rank while the next-highest soldier is merely a Captain.
There's a sub-point to the Fatigue consideration that multi-segment missions, such as Chosen Stronghold assaults, are treated as multiple missions for Fatigue capping and so SPARKs are worth considering sending to reduce how many people end up Tired or even Shaken, but there's very few such missions, and one of them is the final mission where Fatigue doesn't matter.
The one direct change War of the Chosen makes to SPARKs is that in the base game weapon attachments cannot be applied to the SPARK's cannon, but in War of the Chosen it can be. I'll talk a bit more about that in a bit.
First of all: how do you get a SPARK?
Well, for one thing you need the Shen's Last Gift DLC installed. From there, the details depend.
When starting a campaign, you have 2 relevant options. The first option is to turn on Shen's Last Gift: in this scenario, you'll have to scan a couple of Rumors to unlock access to a special mission with lady Shen herself coming along for the trip, and completing this mission will get you a free SPARK as well as unlock the ability to build more at the Proving Ground. Incidentally, each further SPARK costs 100 Supplies, 2 Elerium Cores, 20 Alien Alloys and 5 Elerium Crystals, as well as taking 14 days with no Engineer assigned to the Proving Grounds. (On Legendary, it costs 150 Supplies, 2 Elerium Cores, 30 Alien Alloys, 10 Elerium Crystals, and takes 20 days to build with no Engineer)
The second option is to turn Shen's Last Gift off when starting a run. In that case, you'll have to perform a Mechanized Warfare Proving Ground Project, which has no requirements beyond the Proving Ground itself. This will take 10 days (5 with an Engineer, longer on Legendary), but it actually costs nothing and gives you a SPARK for free once completed.
If you're playing War of the Chosen, you have a third option: integrated DLC. In that case, you'll actually start with SPARK construction unlocked the instant you've got the Proving Grounds up, but you won't get a free SPARK. Resource crunch tends to be more significant than time crunch up on Legendary, so if you're struggling with Legendary you might consider not turning on Integrated DLC to give you a small edge.
Particularly in the base game and/or on lower difficulties, turning on Shen's Last Gift tends to make the game easier. While SPARKs aren't as much of a pay-to-win superclass as I feared when first seeing them, they do have their quality a bit frontloaded. With the Shen's Last Gift mission on you're not only getting one for free, it's well before you could arrange to research and build one, even if you pretend the sheer cost of building a SPARK isn't, itself, a burden in the early game. The mission is overall a bit harder/more dangerous than equivalently-early regular missions, but not by that much, and the mission is designed so that lady Shen and the SPARK you acquire partway through it are extremely well-suited to handling the mission almost by themselves, so it's not like it's vital you get the right class high enough level to readily cope or anything.
On higher difficulties, the mission's boss ramps up fast enough you might want to put it off for longer, and in War of the Chosen the Fatigue mechanic+Covert Operations makes it harder to squeeze in an extra mission, so in those cases turning on Shen's Last Gift is more of a trade-off than a straightforward boost.
Anyway, the SPARK has a variety of qualities to note right off the bat.
First of all, they have their own statline. It is...
This is noticeably more durable than your human soldiers, and also has slightly higher base Aim, but their Will is poor, though admittedly I'm not entirely sure SPARK Will ever actually matters as they ignore all the mechanics I can think of that use Will.
Rookie difficulty gives them 1 more HP and 10 more Will (For whatever that's worth), but that's it for difficulty effects. Notably, this actually means that climbing up to Commander and then Legendary makes them more appealing, in that your human soldiers are getting more fragile while the SPARK remains just as durable.
One other point: For SPARKs, Strength starts at 0. The vast majority of the time this doesn't matter, as Strength doesn't do anything in and of itself. However, some enemies have abilities whose effectiveness involves a Strength test; in such cases, if the SPARK is susceptible to the effects at all, they are vastly more vulnerable to such effects. You should make an effort to keep the SPARK away from ADVENT Stun Lancers, Muton Berserkers, regular Muton melee reach, and the Berserker Queen, as the SPARK is alarmingly likely to end up Stunned. On the plus side, they can't be knocked Unconscious, so actually in the Berserker Queen's case it may be better to have the SPARK be her closest target just to avoid anyone being knocked Unconscious in an instant, particularly in timed forced-evac missions where the burden of carrying a body to the evac point can be fatal.
On an aesthetic note, SPARKs have a silly Concealment-entering animation at the beginning of a mission wherein their BIT spraypaints a cloaking field on them. Annoyingly, if you have multiple SPARKs, they'll each patiently wait for the previous SPARK to finish its cloaking spraypaint job before starting their own, so even if you go against the grain and insist on SPARK spam you'll find it tedious in addition to dubiously practical. One SPARK's spraypaint animation mostly occurs inside the normal wait period before being given control. Later SPARKs will each add a few seconds to the time you have to wait to start the mission. I don't get this decision.
Anyway, on to ranks.
First of all, SPARKS always arrive at Squaddie -though they have their own knight-themed terminology, and in fact their own custom rank icons! Point is, there's no Rookie SPARKs. Which makes it a bit odd they have a level-up benefit at Squire.
Second of all, while SPARKs don't have an explicit Shredder ability like Grenadiers do, their cannons have an innate Shred scaled to the tech level of the weapon, just like Grenadiers who've taken Shredder. (ie 1/2/3 for Conventional/Magnetic/Beam)
Third, unmentioned by the game itself, SPARKs effectively have always-on Jet Boot Modules from the prior game; they can jump any number of Z-levels to reach new heights so long as there's a location to jump to, no need for ladders, pipes, vines, or other climbing aids. This is a particularly interesting quality, in that SPARKs are clearly Mecs+SHIVs, but both of those were in part defined by being less mobile than your core troops, not more mobile. The one qualifier in this regard is that there are some objects where it's possible to Grapple atop them but inexplicably a SPARK cannot jet to the same location. Also noteworthy is a subtle change between the previous game and XCOM 2 is that in the prior game climbing up a pipe or ladder or whatever was a free action that cost no movement, whereas in XCOM 2 doing so actually uses up a fair amount of a soldier's movement, making it difficult to climb to a good position and shoot in the same turn. The relevancy of this change is that the SPARK is not affected by it, allowing them to casually go wherever you need them. This makes it much easier for SPARKs to achieve height advantage than your other troops, when the option exists, especially in conjunction with...
Fourth, SPARKs are much like Mecs or SHIVs from the prior game in that they can't make use of Cover, making up for it with some innate Defense, high HP, and immunity to the crit bonus normally suffered from being in the open. Plus Armor, though that's a new mechanic. This comes with the caveat that SPARKs do still use Cover for Concealment purposes. As such, during the initial Concealment phase of a mission, you should endeavor to have your SPARKs move as if they were human soldiers, albeit with the caveat that High Cover should be reserved for other soldiers. Once Concealment is broken, though, the only relevance of Cover is that High Cover tends to break line of sight/line of fire, and as SPARKs don't perform step-out like your other soldiers this means the SPARK can hide behind a cactus or the like where a human soldier would remain vulnerable to fire. Bringing this back to the original point, their inability to use Cover also means they can freely take advantage of high ground even in cases where no convenient Cover exists, since they don't care about the lack anyway. This is particularly commonly helpful with natural cliffsides, but you also get ADVENT towers that can be stood atop but lack Cover. You might also expect it to apply when attacking ADVENT convoys, since these are frequently on flat ground with the only high points being the vehicle tops themselves, but vehicle tops are one of the examples where you can Grapple but not jetboot. This is sad, since those never have Cover. Ah well.
Fifth, SPARKs never have any utility Item slots. This is one reason they're not as much of a super-class as you might expect; your human soldiers are better able to be customized to combat the threats the Shadow Chamber is forewarning you of, and just generally have access to a lot of capabilities and modifiers SPARKs do not, such as damage boosts from Ammo Items.
Sixth, SPARKs can never use Personal Combat Sims, not even in War of the Chosen. This... isn't that important given that Sims are generally very minor, particularly past the early mid-early game, but it's another thing that makes them a little less good than they might first seem, particularly in the base game where you can reliably boost PCS effectiveness via the Guerrilla Tactics School. (In War of the Chosen, you have to luck into it as eg a Continent Bonus)
Seventh, SPARKs do not get to participate in body-carrying. They can't carry bodies themselves, and their bodies can't be carried. This means that in Extraction missions SPARKs that die have any gear on them irretrievably lost (Which admittedly is limited in its impact, since they can't carry most loseable gear), and it also means any dreams you had of a 100% SPARK gimmick run have been crushed before they could get off the ground, as the game cannot be completed without body-carrying capacity.
Eighth, SPARKs relate completely differently to injuries. Unlike your regular soldiers, they don't passively heal over time; instead, you have a single slot in Engineering SPARKs will assign themselves to when injured, which heals them for free. On the plus side, you can send SPARKs out even if they're injured regardless of mission type, but this still makes it impractical to try to stack up on SPARKs; one SPARK is effortless to fit in your team. Two SPARKs will occasionally require you sideline one for a while because they both get badly damaged and you can't repair them both at the same time. Three or more gets quite unwieldy unless you're really reliable at preventing them from taking damage in the first place.
Ninth, when SPARKs do get injured, they actually bounce back more readily than your other soldiers. Assuming they survive a mission, they immediately restore some health at the end of a mission. I'm not sure the precise numbers, though the wider internet says they gain 2/4/6 HP based on their armor tier and that sounds plausible. As such, while SPARKs are actually surprisingly frail at high levels, it's still usually better to have them soak a stray hit than one of your other soldiers who won't recover as readily, and indeed you can potentially get away with having a SPARK knocked down to 1 HP and then turning around and sending it out almost immediately afterward, as they can bounce up to a respectable value fairly quickly due to this mechanic.
This unit is a robot, rendering it immune to Poison, Fire, and Chryssalid Poison as well as most psionic or mental effects (Including that it will never Panic or be rendered Unconscious), but susceptible to anti-robot effects and impossible to heal with Medikits.
Note that SPARKs are not immune to Acid.
Mechanical Chassis makes SPARKs good scouts if you suspect Chryssalids are burrowed ahead and you don't have better options like a Bladestorm Ranger or Templar, and also makes it a bit more palatable to perform area denial with Gas Grenades or Incendiary Grenades, as a SPARK can dash through if for some reason you unexpectedly need a unit to go through the area you've flooded with gas/set on fire. (Such as because an enemy dropped loot and you don't want to wait for the gas/fire to clear before grabbing it)
The robot weaknesses aspect isn't a terribly relevant concern, conversely. It can absolutely crop up through Mind Control, but there aren't any enemies that can perform remote hacking, let alone on hostile robots, and no enemies have innate passive or active abilities in the vein of Bluescreen Rounds or EMP Grenades. As such, this is almost purely an advantage...
... with the caveat that SPARKs are good at absorbing damage but can't be healed by your Specialists. There's a solution available, but it requires your SPARK is leveled a bit, and you're missing out on an alternative option so it's not perfect.
Also note that SPARKs cannot be Shaken in the base game. Again, as far as I'm aware Will on a SPARK doesn't matter so that doesn't matter, but hey. Completion's sake. By a similar token, all the phobia mechanics War of the Chosen adds are, as far as I'm aware, completely irrelevant to SPARKs.
The SPARK's BIT carries a Heavy Weapon.
This is particularly significant if you turn Shen's Last Gift on and hit it fairly early, allowing you access to Heavy Weapons well before you would normally unlock access to them. Just keep in mind that anything other than a Rocket Launcher will be lost forever if your SPARK takes it into a mission you Extract from and they go down in it.
Otherwise, this is functionally identical to a regular soldier equipping one of the heavy Armor types that gives Heavy Weapon access. Just with a different silly animation. The main point worth noting here is that depending on which option you picked unlocking SPARK access won't necessarily give you Experimental Heavy Weapon access, and so you won't necessarily be able to use non-Rocket Launcher Heavy Weapons until you've built an E.X.O. Suit or the R.A.G.E. Suit.
In any event, this is another example of SPARKs being front-loaded, as a SPARK acquired very early will blow the rest of your troops out of the water for ability to vaporize Cover, Shred enemies, and inflict damage in an area. Then you start unlocking the heavy armors and suddenly the SPARK is actually behind everyone else, because they still have the ability to carry a grenade on top of a Heavy Weapon.
The SPARK's BIT may remotely hack standard hackables. 1 turn cooldown.
This is functionally identical to a Specialist's ability to remote-hack with a Gremlin, including that it can be targeted at Security Towers.
However, SPARKs never get Haywire Protocol, and even if they did their Hack score will never rise above a measly 25 (And only that much from their BIT being upgraded) unless you get lucky with one of the 'permanently raise the hacker's Hack score' rewards. As such, the SPARK's ability to remotely hack should only be taken advantage of to handle objective hackables (The kind where nothing bad can actually happen for failing the roll), and even then ideally you still won't use SPARKs for it because anybody else will be more likely to actually collect a bonus reward.
This is one of the capabilities that had me initially worried SPARKs would be a super-class; they're stealing one of the Specialist's key qualities, on top of stealing the Grenadier's unique role in Shredding with their gun? In actuality, though, SPARK remote-hacking is so close to worthless I'm not sure why the devs gave them it at all. It can occasionally be useful for handling a Hackable objective before it times out, particularly if your Specialist can't spare action points, but that's about it.
A completely free action which immediately grants an additional action point to the SPARK, and makes it so that most actions will not end the turn. Each time the SPARK performs a standard shot in a turn while Overdrive is active, it will suffer a stacking -15 to Aim on any further shots in the turn. Entering Overwatch will still end the turn. 5 turn cooldown.
This could be reasonably accurately viewed as the SPARK's proper squaddie-level skill, equivalent to Squadsight on Sharpshooters or the like.
The in-game description claims that 'no action' is turn-ending, but this is flatly incorrect, as Overwatch will still end the SPARK's turn. This is a bit surprising given that Specialists can gift Overwatch to a soldier without it ending their turn, and makes Overdrive a little bit less useful for supporting an Overwatch ambush.
While you can use it multiple times in a mission, a SPARK really needs to get to a higher level before it starts being useful to use it more than once. At base, the main use is to fire a Heavy Weapon, move to flank, and take a shot. Or occasionally take two shots. That's about it, though.
Note that Overwatch shots do trigger Overdrive's penalty. As such, if you don't have Adaptive Aim on your SPARK you should be careful about how you time Overdrive and Threat Assessment Aid Protocol on a SPARK; if you're going to use Threat Assessment Aid Protocol to gift your SPARK a reaction shot for the purposes of an Overwatch ambush, you should Overdrive after the ambush has been triggered, so they don't get hit Overdrive's penalty unnecessarily. So for one thing don't try to have the SPARK kick off the ambush with an Overdrive-backed shot in that situation; have someone else take the first shot.
I'll be coming back to Overdrive a few times over the course of this post, note, as it ties into a lot of the SPARK's other skills one way or another.
You might notice I still haven't listed an HP gain. That's not an oversight on my part: SPARKs never gain HP from leveling. They're completely reliant on upgrading their chassis to boost their survivability, which means that in the late game they're surprisingly frail, as the SPARK's third-tier armor actually provides less HP than a W.A.R. Suit. They can consistently beat out human soldiers when it comes to the Armor stat, but late-game SPARKs are much more about their astounding mobility and very good firepower than they are about tanking hits.
Incidentally, the SPARK's two lanes are 'Future Combat' and 'War Machine'. The general theme is defensive vs aggressive; 'Future Combat' skills usually encourage you to put the SPARK into a position to absorb punishment for its teammates, while 'War Machine' skills are generally more glass-cannon-y. In every case, I'm listing the 'Future Combat' skill first and the 'War Machine' skill second.
+1 Armor, and the SPARK counts as a Full Cover element on all sides.
Note that, just like with Alloy SHIVs in the prior game, Bulwark causes Cover-using enemies adjacent to the SPARK to get the Full Cover benefits against the SPARK itself. As such, if you like to hurl the SPARK into the fray, Bulwark is more of a mixed bag than you might expect, potentially slashing 40 of the SPARK's Aim at an unfortunate moment.
On the other hand, Bulwark interacts in a very silly way with Concealment rules, letting you stack up rows of SPARKs behind a single piece of Cover because they're each hidden by the SPARK in front of them. Most maps make this unnecessary, but this can occasionally let you set up ambushes in locations you really shouldn't be able to.
More generally, Bulwark is a pretty general way of bolstering the SPARK's survivability, and is particularly worth considering if you like to use your SPARKs to trip Chryssalid landmines. It's also useful for letting you safely move up human soldiers even in map chunks that lack good Cover options to hop to, though beware the possibility of explosives being tossed at the two.
Note that Bulwark is slightly glitchy when it comes to having the SPARK evac. It'll often be the case that units can take cover against nothing at all, as if the SPARK was still where it was standing before it left the battlefield. The especially weird thing is that usually units will still be able to enter the tile it last was in. Only usually, though; sometimes it'll also be impassible to units. This generally isn't an important glitch given that most of the time you'll try to evac everyone in the same turn, but it can have some odd consequences if things are coming apart and you're scrambling to get everyone out.
And no, War of the Chosen doesn't fix this glitch. Or any of the glitches regarding the SPARK, as far as I'm aware. I meant it when I said War of the Chosen largely avoid changing the SPARK.
Overdrive shots no longer accrue Aim penalties for successive shots.
In the base game, Bulwark is probably the better choice. The SPARK only has three shots in their weapon, which makes it really difficult to arrange to fire a full three Overdrive shots; an Overwatch ambush is basically the only time you're going to be able to line things up like that, and often in such situations you're better off using one of the SPARKs actions to blow up Cover or re-position to flank something instead of taking the full three shots anyway. This only gets worse as you level up and pick up other options for leveraging Overdrive actions, further disincentiving taking advantage of Adaptive Aim.
War of the Chosen vastly improves its viability. First of all, Expanded Magazines mean that catching a pod wandering into sight with an Overwatch shot doesn't instantly deny you the ability to do a full Adaptive Aim stream. Secondly, Hair Triggers synergize with Adaptive Aim; Hair Triggers can semi-reliably lead to additional shots in a full Overdrive chain, which without Adaptive Aim will suffer from increasingly crushing Aim penalties. Third and more debateable is that Repeaters give a greater incentive to focus on shooting things and require actually hitting the target to trigger. Fourth and more subtle is that Superior Scopes let you bolster the SPARKs Aim to a full 100 without needing to burn an action on getting close enough for Aim climb to happen, making it so that as long as other soldiers handle the job of ripping enemies out of Cover your Adaptive Aim SPARKs can 100% reliably dakka things. A tertiary point is that Skirmishers can, in fact, gift action points to SPARKs, providing another avenue for having a SPARK fire even more times in a turn, potentially risking Overdrive penalties if you don't have Adaptive Aim.
Bulwark is still a competitive choice, as a point of Armor can be quite valuable and the High Cover effect can combine well with using human troops aggressively, but it's a much more even choice, and probably actually slanted a little in Adaptive Aim's favor simply because you don't need Armor if everything is already dead.
All Heavy Weapons do +2 damage and have expanded area of effect.
The area-of-effect expansion is +2, except for some reason the Plasma Blaster only gets +1. Note that with cone attacks this is both +2 to the maximum range and +2 to the width, aside the Plasma Blaster only being +1 in each case.
Rainmaker isn't bad, but it's a little boring and damage per se doesn't tend to be the draw of Heavy Weapons. It also doesn't scale well with later Heavy Weapons, as its damage is fixed and the radius expansion is often not meaningfully useful when talking eg a Blaster Launcher. As such, I have a fairly strong preference for...
The SPARK performs a move-and-melee strike on a single target. This strike has +20 to Aim, and does 7, 9, or 11 damage based on the SPARK's chassis tier. Crits will add 2 damage in all cases. 4 turn cooldown.
Strike is another skill that had me worried the SPARK would be some omniclass displacing all your human troops, what with obviously overlapping with Slash's utility. Fortunately, while Strike is strong and accurate, the harsh cooldown forces you to use it more strategically than a Ranger uses Slash.
One of the better uses of Strike, particularly for a SPARK who took Bulwark instead of Adaptive Aim, is to re-position during Overdrive without missing out on an offensive action, allowing you to flank one enemy by punching another. This is especially relevant in the base game where Adaptive Aim is difficult to justify, but even in War of the Chosen it's a great utility to have sitting around when you want it.
Note that if your SPARK took Bulwark, you should make a point of attempting to Strike from corners to avoid giving the target Cover benefits from your SPARK. Melee doesn't care about Cover, mind, but if the SPARK misses the strike or you were using it to soften something up, you don't want to have accidentally given your victim High Cover in the process of punching their lights out.
Note that the +20 Aim Strike gets is enough to immediately place Strike at a 99% chance to hit targets with 0 Defense. After a level-up, it's a guaranteed hit against targets with 0 Defense. This makes it useful for finishing off targets with Dodge and no innate Defense, such as a Codex or Viper.
Also note that Overdrive's Aim penalty actually affects Strike's accuracy. As such, for a SPARK with Bulwark instead of Adaptive Aim it's generally best to place Strike early in Overdrive order if at all reasonable, as Strike itself doesn't stack onto the Overdrive Aim penalty.
Every time the SPARK is targeted by an effect, whether it's a ranged, melee, or area-of-effect attack, the attacker has a chance to Panic. Overwatch fire does not trigger this Panic chance. The Panic chance is 25%/40%/55%, based on the tier of chassis the SPARK is equipped with.
Now you are the Muton!
Note that Intimidate doesn't roll against Will. It's just a flat Panic chance. A lot of enemies are incapable of Panic, so that's less ridiculous than it might first sound, but it means it will work fairly reliably against enemies you might've expected to be resistant.
It also comes up more often than you might expect, assuming you're using one SPARK mixed in with a bunch of human soldiers, as while SPARKs have innate Defense it's less than what even Low Cover provides and the AI does actually have a preference for targeting whoever it's most likely to hit. As such, the SPARK will draw a disproportionate amount of fire if you don't regularly stand your human soldiers in the open. This comes with the caveat that if you're not playing on Legendary the AI has a strong collective preference for trying to spread damage around your team instead of focus-firing someone, but that just means that without Sacrifice you can't expect the SPARK to draw all the fire in a given turn.
Note that where player units Panicking have random behaviors, Alien/ADVENT forces that Panic have a very predictable response: they immediately take a shot at one of their own allies. This is very silly, frankly, but it at least ensures Intimidate triggering has no chance for a backfire. This is good on a game design level, because otherwise Intimidate would be basically a trap choice. (Caveat: for some reason Mutons in particular have a nasty habit of reacting to Panic by trying to chunk their Plasma Grenade at your forces)
As-is, I personally rate Intimidate as much weaker of a pick than the alternative at this level, no matter what you're having your SPARK do with its other level-ups, but it's theoretically the better pick if you're not tending to get close enough to actually benefit from Wrecking Ball. War of the Chosen also makes things slightly more favorable to Intimidate, but I'll get into that in Wrecking Ball's section.
Also, Intimidate's animation is very silly and I have no idea why playing some blue lights at an enemy is supposed to freak them out.
When Overdrive is active, the SPARK can freely move through destructible terrain, destroying it in the process.
Did you know XCOM 2 has a waypoint system? Simply press ctrl when right-clicking to set a waypoint! Set as many as you like, at least until you run out of movement!
This has its uses in general, such as letting you path a unit to avoid triggering Overwatch fire or convince a unit to stop trying to path through fire/acid/poison gas (They usually try not to, but occasionally the pathing will unnecessarily insist on it anyway), but is particularly important to remember when taking advantage of Wrecking Ball, letting you ram through multiple units' Cover when single-clicking would only let you catch a much more limited portion of Cover.
Also remember that Wrecking Ball works particularly well with Strike, letting you avoid 'wasting' an Overdrive action on just moving. Want to punch a hole through a wall in an Avatar Project facility? Strike someone on the other side of a wall, maybe having used waypoints to smash through whichever wall chunk you want to smash through, then commence shooting at the unfortunate enemies you're now flanking.
One of the more important benefits of Wrecking Ball is that it's reusable and fairly unconditional; most on-demand terrain destruction effects are single-use grenades or Heavy Weapons, and the exceptions are often unreliable. (eg Saturation Fire, Demolition) Thus, taking it gives you the ability to wreck Cover with minimal mid-term sacrifices involved; that is, instead of lobbing a Plasma Grenade at a wall to punch a hole in it, and then regretting it when you don't have any grenades left to help Shred a Sectopod, you can just Wrecking Ball the wall instead.
That said, Wrecking Ball isn't coded perfectly. Solid walls will be smashed very reliably, but Low Cover terrain objects and not-Cover-but-still-impassible terrain objects will frequently be walked right through without affecting them. (I imagine this is a consequence of how such objects can normally be walked on, including by SPARKs) Don't count on the terrain destruction outside of Koolaiding through solid walls. (Note that it's still useful for letting the SPARK path through regions it might otherwise be unable to path through, even if they glitchily fail to be destroyed. This is niche, but nice when it's available)
Wrecking Ball is particularly easy to justify taking in the base game, where it's difficult to arrange a full three shots in a row from an Overdrive, and so you're quite likely to take Overdrive movement actions even ignoring Strike. Making them smash Cover makes those otherwise somewhat wasteful movement actions potentially a lot more useful. In War of the Chosen, the ability to attach an Expanded Magazine and/or Autoloader makes it a lot easier to chain shots, at which point a well-supported SPARK is pretty unlikely to perform an Overdrive move without specifically using Strike, bar the possibility of you feeling it's worth giving up a shot to smash through some Cover in a particular situation. As such, if you liked the idea of Intimidate but found it underwhelming in the base game, you should consider giving it a try again in War of the Chosen, simply because Wrecking Ball is a lot less likely to end up leveraged unless you go out of your way to leverage it.
Sends the BIT to repair a target robotic ally. By default has 2 charges, each of which repairs 6 HP.
Note that the in-game description claims that higher-tier BITs improve the amount of healing Repair provides. Also note that this is a lie, and Repair will in actual fact always repair exactly 6 HP, or less if the target is missing less than 6 HP. It's strange how this was never caught, not even into War of the Chosen.
To be clear, Repair functions exactly as Medical Protocol does, but for machines. You can target any valid ally anywhere on the map, regardless of lines of fire and so on, including yourself. The insane range potential is, mind, much less consistently useful for a SPARK than for a Specialist since the default expectation is that you're using one SPARK... but if you do use multiple SPARKs, it can be quite nice.
Unsurprisingly, this goes off the same basic rules as a Medikit; if a SPARK gets knocked down to 1 HP, even if you then Repair it to full it's going to require as many days to repair itself after the mission as it would take if you didn't Repair it at all.
Regardless, if you want your SPARKs regularly soaking damage for the team, you're going to want at least one SPARK carrying Repair to top them off mid-mission.
You can technically also use Repair on other machines, but I'm having difficulty imagining a legitimate use for this in single-player. The only other player machines are the Avenger Defense X-COM Turrets (Which you have basically no incentive to be repairing), and hacking an enemy robot only temporarily takes it for your own use. You're much more likely to destroy a hacked robot yourself than to want to Repair it.
Personally, I have a fairly difficult time justifying taking Repair. If you commit to a really SPARK-heavy run (As in 4+ SPARKs as your A-team) you should probably take it on a couple of SPARKs so they can keep the force reasonably fighting-fit, but the SPARK mechanics heavily discourage stacking SPARKs and especially discourage stacking SPARKs while trying to use them in a way that risks damage to them; I'd generally rather take Bombard, since dead enemies are enemies that can't hurt the SPARKs and force post-mission repairs in the first place.
That said, one notable use of Repair is that it can be taken if you want to ensure you can keep bringing SPARKs into missions even when badly damaged without risking being killed. Using Repair doesn't break Concealment, doesn't end the turn, and 12 HP worth of repairs is more than 2/3rds of even third-tier chassis HP, in conjunction with needing at least one HP to still be alive. This is particularly relevant if you do elect to give a SPARK-heavy run a shot, since it can partially compensate for the inability to have multiple of them repairing outside of combat; simply send them in and Repair them before combat starts.
Repair is a surprisingly weird skill for being a reskinned Medical Protocol...
Launches the BIT at any location any member of the squad can currently see, hitting in a 3-tile wide radius for 3-4, 5-6, or 7-8 damage (Based on BIT tier) and destroying all destructible terrain objects in its radius. Can pass through ceilings on the way out and in, and will cause damage to them in the process. 1 charge.
AKA 'basketball of death'.
Note that the damage is an example of +1 mechanics in action; in each case, the higher damage value has only a 25% chance of occurring. As such, you should essentially plan around Bombard's damage being its lower value, rather than gambling on a high roll.
Bombard is an excellent 'panic button' move, allowing the SPARK to assist the team with any number of problems no matter how badly out of position they've ended up being, as well as offering you an option for wrecking Cover even if nobody else is both in the right position and equipped with relevant gear/skills. Ideally you'll look for other such options first, so you'll have Bombard available for when you need it, but when you do need it it's fantastic.
Bombard is also a bit counterintuitive, as it fits the profile normally useful against hard targets, but in actual fact is much better against soft targets, lacking Shred and being most useful for its supreme effectiveness at Cover-wrecking. (Which is generally most relevant against soft targets, since most hard targets can't take Cover in the first place) One exception to this is that Bombard is one of the best, most reliable ways to wreck floors where applicable, and so can be used to knock Turrets down for a fall-based kill; this is particularly useful if you've got a couple of Turrets clumped close enough to catch them both and can't spare the squad effort to kill them more conventionally.
A fiddly mechanics point is that Bombard is precise in an unintuitive manner for its targeting capability. To be able to target a location, you have to have line of sight to the center tile, and you have to have it right when you want to launch the Bit. The game only cares about the center tile, so you can absolutely use it to hit targets you know exist but currently lack line of sight on, but conversely you can get cases where you, the player, can see a tile, but none of your troops is considered to have line of sight on it so the game won't let you fire Bombard at that spot. As the game provides absolutely no error message whatsoever when you can't target Bombard at a location, this can lead to frustration as you spend several seconds wondering why the game isn't accepting your input. No, it's (probably) not crashing or otherwise having a freakout. You just need to find a different tile to target.
Each time the SPARK is fired at, it gains +1 damage to its next standard shot. This effect is expended even if the SPARK's next shot misses.
On the plus side, this is 'shot at', not 'successfully hit'. On the minus side, good play is centered around not getting shot at in the first place, and Channeling Field's effect doesn't scale with weapon quality or chassis tier or anything. If you turn on Shen's Last Gift and take Channeling Field on SPARK-001 having used it as consistently as possible, you might find it okay in the early-to-midgame, but it gets less and less relevant as the game goes on. This gets even worse in War of the Chosen, where Breakthroughs can add another point of damage to the SPARK cannon and so make an additional point of damage that much less relevant, proportionately.
If it was at least an effect that lasted throughout your next turn, instead of specifically on your next shot, it could be a nifty combo with Adaptive Aim, but overall I just have a hard time imagining why you'd actually want Channeling Field. If you plan on taking Sacrifice it gets a bit better, since Sacrifice is a tool for actually directing enemy fire at the SPARK, but that's one of your few reliable ways of arranging to direct enemy fire at the SPARK in particular.
Part of the problem being there's not really any enemy type that's based on multiple weak shots. If there were enemies vaguely equivalent to a Sharpshooter who has dedicated theirself to Pistol use, then Channeling Field would potentially be a powerful boost to damage when such enemies were running around; you might have one SPARK take Channeling Field and send them into any mission the Shadow Chamber indicated such an enemy was in. The closest the game comes to this is Turrets, which... aren't really an example for a few different reasons. Another part of the problem is that attacks always do at least 1 point of damage, even if the target has more Armor than the attack, so a flurry of weak attacks would actually still be alarmingly dangerous to a SPARK!
The other big problem is that Overwatch is surprisingly rare to run into. If it was a regular thing for enemies to be in Overwatch, you could do stuff like Aid Protocol your SPARK and then have them move to trigger multiple Overwatch shots, and then redirect all the acquired energy on whatever big nasty you wanted. In practice, you largely have to rely on the whims of the AI.
You know, when you even let them get a turn.
As such, while Channeling Field is a mildly interesting idea, it's a very lackluster ability in practice, and you should probably always skip it, particularly considering what it competes with.
If an enemy first activates within the SPARK's line of fire, the SPARK has a 33% chance of taking a free Overwatch shot at that unit, assuming the unit actually moves.
The in-game description talks about when an enemy is 'revealed', but Hunter Protocol won't activate as long as the SPARK is Concealed and will activate when you break Concealment and have enemy pods activate in response. Also note that 'first activates' is fairly generously defined, as an enemy can activate outside of the SPARK's personal awareness and so long as their first pod activation-move at any point passes through an area the SPARK has line of fire on Hunter Protocol is allowed to trigger.
Hunter Protocol is thus a nice little bonus during Overwatch ambushes -among other points, I'm reasonably confident it benefits from the 'Overwatch shots operate at full Aim during an ambush' effect.
Hunter Protocol is, in the base game, yet another knock against Adaptive Aim, which is particularly annoying since they're under the same lane and the clear premise of skill lanes in XCOM 2 is that running down a given lane is supposed to be synergistic across the skills in the lane, rather than anti-synergistic. After all, it makes it that much harder to have ammo ready for a three-shot burst. Thankfully, this issue goes away in War of the Chosen; just attach an Autoloader and/or Extended Magazine, and Hunter Protocol triggering isn't instantly taking away your ability to do a full Adaptive Aim burst that turn. Still, in the base game if you've taken Adaptive Aim you might want to pick Channeling Field just so you can more consistently get use out of Adaptive Aim.
More likely is that you take Bulwark and then Hunter Protocol, though.
Hunter Protocol is, incidentally, the other reason I have trouble justifying Channeling Field. Sure, I could occasionally get a whole extra point of damage through circumstances that, while not random in the straightforward sense, are difficult to directly control and still influenced by randomness... orrrr I could occasionally get multiple extra points of damage through more straightforward randomness. The issue only gets worse as your technology improves, since Hunter Protocol directly scales to your weapons technology while Channeling Field is stuck at a measly +1 per attack at you no matter what. Bonus points: Hunter Protocol activates exactly when you most want additional firepower. Channeling Field... not so much.
If Channeling Field were competing with something that wasn't fairly close to 'the same basic end result, but better', I'd be more inclined to take it. This isn't on the level of, say, Holo Targeting vs Bullet Swarm on the Heavy in the previous game where it flat-out was not a choice at all, but it's a lot more badly biased than most XCOM 2 skill choices are.
And since SPARKs don't benefit from the Ability Points system, it's not like you're going to buy it on your favorite SPARK in War of the Chosen, the way you might buy everything on a favorite soldier of almost any other class.
On a different note, an edge case interaction is that Hunter Protocol triggering while Overdrive is active will suffer from and exacerbate the Overdrive Aim penalties if the SPARK lacks Adaptive Aim. As such, if you're planning on taking Hunter Protocol it's that little bit more important to take Adaptive Aim, assuming you're playing War of the Chosen where Expanded Magazines can lead to extra-long shooting chains. I mean, it applies in the base game, but in War of the Chosen you can fairly readily end up firing shots at -45, -60, -75, -90... you know, complete wastes of ammo. The base game can only get those kinds of numbers if you specifically fire twice, reload, and then have Hunter Protocol start triggering, and that can only hit -75, and only if you fire twice, reload, and then have Hunter Protocol trigger three times. Which you're not likely to do, let's be honest.
A weird sub-point of this is that it's possible to end up with Overdrive penalties from shots your SPARK didn't take through the Hunter Protocol, as the game seems to roll for Hunter Protocol triggering and assign the appropriate Aim penalty independent of whether the shots were actually fired. I've only specifically had this happen by having my SPARK go into Overdrive and fire a Rocket into a Claymore, killing enemies that were guaranteed to survive either of the Rocket or Claymore but doomed to die to both, so this probably isn't something you have to worry about unless that's a regular game plan for you... but if it is, you might want to endeavor to take Adaptive Aim on any SPARK you intend to take Hunter Protocol on.
Jank aside, Hunter Protocol is a great ability all-around, and a fairly interesting one. I don't even mind that it involves a strong element of randomness, as the form the randomness takes is a good fit to the gameplay.
Do note that requirement that the activating enemy move. This is mostly not an issue, but it does mean Hunter Protocol will usually not trigger on ADVENT Heavy Mecs, which is slightly inconvenient since they're one of the better enemies to have your SPARK getting a free first shot at.
A max-level SPARK's Aim is actually one of the betters ones on your soldiers, enough so that simply taking high ground will ensure they hit a target standing in the open that has no Defense. Or you can have your SPARK standing adjacent to the target, either/or.
Unfortunately, on Legendary many enemies have an innate 10 Defense, so without some manner of Aim boosting SPARKs will always be somewhat unreliable. This is particularly concerning in the base game where it's simply not an option to equip them with a Scope, though even into War of the Chosen it's still an issue that they can't use a Perception PCS and it also hurts them that they're barred from the new Covert Op mechanic and thus can't get the Aim boosts Covert Ops can provide.
Ideally, you'll have Holo Targeting support if you intend to use SPARKs, basically. This is somewhat amusing, since Grenadiers are the class they come closest to putting out of a job... but Grenadiers are the class that has reliable access to Holo Targeting.
The SPARK moves to a targeted location within its current movement range and generates a 4-tile-out protective field that redirects all enemy fire from allies that are inside the field to the SPARK itself. While Sacrifice is active, the SPARK gains 2 Armor and 20 Defense. 4 turn cooldown.
Sacrifice also has some invisible benefits, causing enemies to refuse to use certain abilities on units in its radius. One of the most notable is that Vipers and the Viper King won't use their tongue-pull attack on Sacrifice-protected units, nor Bind them, but it also prevents Gatekeepers from eating your troops' HP, prevents Suppression-capable enemies from Suppressing anyone under the shield, and also prevents the Archon King from trying to grab your troops. Aside Suppression, blocking these can be lifesavers!
As with most move-and-activate effects, Sacrifice's maximum distance is based on the user's current Mobility and number of available moves. This is particularly pertinent when considering combining it with an Overdrive, as it means you may find that firing twice leads to you being unable to Sacrifice at the location you want to Sacrifice at.
Personally, I don't rate Sacrifice very highly. It's rarely practical to clump up your soldiers such that you can cover them with Sacrifice efficiently, just in terms of Cover placement, and even if it were it's a bad idea due to the risk of provoking splash damage attacks like Micromissiles, which completely bypass Sacrifice. Late-game enemies hit hard enough that even with Bulwark and a max-tier chassis the SPARK doesn't like taking a hit at all, and the +20 Defense from Sacrifice puts the SPARK at a measly 35 Defense total; most enemies have at least 70 Aim, so the SPARK has a better than 33% chance of being hit by most given attacks, more if enemies are attacking from high ground or just have good innate Aim. Your human troops in High Cover are actually better-protected on the Defense level, and in the late game they can actually soak similar or greater damage than a SPARK just in terms of HP+Armor.
Sacrifice would've had to be more on the order of temporary invulnerability to readily justify itself. It's a cool idea, but I have difficulty imagining a situation in which it's actually a good pick.
A completely free, instant-use attack that does 6 damage to all units within 3 tiles of the SPARK. Has no cooldown, but each time Nova is used it will do 0+2 damage per use to the SPARK, with this self-damage only resetting once the mission is over with.
3 tiles is not precisely accurate, as strangely the targeting doesn't go out 3 tiles in a straight line along the cardinal directions the way most splash effects do, resulting in a square with its corners cut off.
Nova is a weird skill. On the one hand, it is completely, 100% free on the very first use in a mission. On the other hand, since the self-damage ramps up as you abuse it, it's not actually the case that you go 'oh, this is an okay situation to use it, might as well zap these enemies right now since it's free'. After all, what if you want to use it later? This can result in situations where you repeatedly could have derived a lot of benefit from Nova, but held off Just In Case, and the time you feel justified in using it never quite arrives.
I think Nova is probably the better skill to take in practice, simply because offense is usually better than defense in XCOM 2 and Nova's completely free nature means that it doesn't have to worry about problems like 'I wanted to use Strike, but that would've meant not firing my gun!' Buuuut that comes with the qualifier that player psychology is a really important factor; if you're the sort of person who holds onto Elixirs Just In Case in JRPGs, odds are good you'll take Nova and then just keep failing to use it at all. At that point you might as well take Sacrifice, since you'll actually get benefit from it. (Well, theoretically...) If, on the other hand, you're easily able to go 'yeah, there's like three Chryssalids on top of my SPARK, let's zap 'em', then yeah it's probably genuinely the better choice.
It helps that 6 damage is a pretty solid amount of damage to be doing in an area, staying decently relevant even into the late game.
Narratively, SPARKs are weird. Papa Shen had Mecs dreamed up, but never performed a practical execution! Then he apparently decided he didn't like cybernetics, so he made a fully-functioning robot that's battlefield-relevant 20 years in the future using no or minimal Alien technology, but for some reason set it so his daughter would have to manually activate it and never mentioned to her his secret robot project only she can activate!
Like, I get that it's DLC and the devs are trying to basically make non-DLC and DLC runs equally 'canon' (ie non-DLC runs just happened to not find the facility with SPARK-001), but the whole thing doesn't hold up to scrutiny and it just feels very unnecessary. The enemy is already fielding fully-functioning combat robots inexplicably based on papa Shen's Mec designs, lady Shen already treats her personal Gremlin like it's a person or at least a beloved and smart pet, it's not actually a giant leap to go from there to taking ADVENT Mec Wrecks and salvaging them to produce an X-COM-friendly Mec, and it would avoid all the silliness of this whole plot and make the world feel more real and interconnected.
It could also be connected to character stuff more naturally, such as having lady Shen find out that ADVENT Mecs are based on her father's design and going the conversion route over outrage that a tool designed to fight Alien oppression was co-opted to further the Aliens' ends. Which would also in turn make it more tolerable of a plotpoint that papa Shen's Mec design did get co-opted by the Aliens; suddenly that's not a random, nonsensical plotpoint that has no reason to exist. I mean, it'd still be pretty nonsensical, but it would have a reason to exist, which would make the nonsensicalness more forgivable.
Alas, we get this bundle of missed opportunities instead.
Mechanically/gameplay-thematically, SPARKs are the inheritor of the Mec's will with a side order of SHIV-ness to them, but without all the reasons SHIVs were terrible. Many of the SPARK's animations are straight-up recycled from Mecs, such as Strike being pretty blatantly the Kinetic Strike Module punch animation, just with less ridiculous ragdoll physics on killed targets. This is interesting in part because it's part of a broader narrative trend in XCOM 2 of walking back the pro-transhumanist themes from the prior game; our Mec-equivalent is a robot instead of a cyborg, Gene Mods are gone, psychic powers are no longer a straight plus stacked atop everything you could already do... the only maybe-pro-transhumanist element in XCOM 2 is Personal Combat Sims, which as far as I'm aware what they actually are is never directly addressed by the game, though they seem to be intended to be some manner of brain-chip. If so the pro-transhumanism isn't gone entirely, but it's been heavily walked back for sure.
Regardless, it's interesting to me XCOM 2 reverses that trend, given it's a futuristic semi-post-apocalypse cyberpunk-ish story, which is normally exactly the kind of story that heavily incorporates transhumanism. (Generally to paint it in a bad light, mind, but still) Especially with how it connects to some other things, but I'll talk about that more later.
More purely mechanically, it's worth noting SPARKs are actually a little underwhelming in War of the Chosen. They still have uses, but the core classes are massively boosted and the new classes are generally more super-class-y than SPARKs, where SPARKs have mostly gotten a mild, somewhat situational boost through gaining access to weapon attachments. In the base game, it can be really hard to justify not taking a SPARK for a good chunk of the game; in War of the Chosen, it's easy to end up filling out your team, notice no SPARK is in it, and then struggle to justify pushing out one of the other soldiers.
On the other hand, SPARKs never tire and can be sent out when wounded, so in War of the Chosen they can be a reliable babysitter for your not-your-A-team squads that can pull them out of the fire when running into situations that are a bit out of their depth, so they're by no means bad in War of the Chosen, just more niche. The fact that they're immune to Daze and a few other Chosen tricks like the Hunter's bleed effect makes their effectiveness as a babysitter particularly appreciated up until the extreme late game (When you've killed all three Chosen) since an unexpected Chosen attack is something they're reasonable well-suited to fighting off.
Skill tree-wise, I'm a bit disappointed by how the defensive tree is actually fairly lackluster first and foremost because SPARKs are, in the long haul, basically glass cannons relative to your human soldiers. It's a weird outcome, and I suspect the devs didn't fully consider the implications of not having SPARKs gain HP from leveling as I don't think the devs actually realize SPARKs are weirdly fragile past the early game.
Still, this is an impressive improvement over the design of Mecs and SHIVs, both of which were deeply flawed in different ways. It's a pleasant surprise, especially since I was going in expecting a pay-to-win superclass.
Next time, we divert from classes to talk about the Training Center as preparation for talking about the Resistance classes.
See you then.