I've played around 300 hours of XCOM 1, and 50 of XCOM 2 [official site], for my sins. I know full well that this does not make me any kind of expert but I'm experienced enough that XCOM 2 has not yet kicked my flabby little bottom. A lot of people are finding the game very punishing though, so I thought I'd try to help - both by sharing my own advice on how to keep your soldiers alive for longer and by inviting anyone else to share their own tips in comments.
This isn't a definitive guide, but instead a grab-bag of assorted wisdom, both early and advanced, that I'm certain will help if you're having a tough time with this wonderful (if sadly malfunctioning) strategy game.
It’s dangerous to go alone
Obvious perhaps, but the single greatest piece of wisdom I can pass on is about the management of action points. Don’t exhaust five soldiers’ movements and actions then send the sixth hurtling forwards into the unknown on their own, because that means there’s no-one to help out in the event they stumble across a new pack of enemies. Late in the game, lone wolves become vaguely plausible – e.g. the Ranger’s Untouchable skill – but done early on it’s simply suicide.
A good habit to get into is to always have a Sharpshooter and/or Specialist still active before you send anyone into the unknown. The former can provide long-range damage, while the basic Aid function of the latter can provide a significant defensive bonus to even squadmates which are half a map away. As these guys rank up, the help they can provide becomes immense – for instance, a Sharpshooter can fire three times in Overwatch, while the Specialist’s flying robot thing can double the defence of Aid. The early Specialist Scanning Protocol unlock is also useful for identifying whether there are any enemies just around the corner.
Explosives can destroy cover, which can massively increase the to-hit chance on any enemy which was hiding behind it, or open up brand new lines of sight to aliens who were sheltering indoors. Very often, it’s smarter to not spend an action on a standard shot that will only knock a couple of hitpoints off a tough enemy or is simply unlikely to land, and instead see if your Grenadier (or indeed anyone with a grenade in their pocket) can rearrange the scenery so the rest of their squad has better odds.
As with the first point, about travelling alone, this ties back to the importance of using your squad in the correct order. Using an explosive to destroy an alien's cover after everyone has already taken an unsuccessful shot might help you out next turn, but you might have lost a couple of soldiers at that point, or the enemy might have moved to a new location with fresh cover. The sequence that your soldiers act in as almost as important as the actions they take.
Explosives have another extra boon: they shred Armor. Those are the cheeky yellow blobs at the end of enemies’ health meters, and for each one of those any shot you land will usually lose one point of damage. So, again, a Grenadier’s bomb might do significantly less damage than a shot from her standard weapon, but it’s worth it if it takes a point or two of Armor away, so the rest of the squad can then score bigger hits. Don’t even think about taking on a Gatekeeper or Sectopod without softening it up with explosives first.
Overwatch is the bedrock of XCOM: banking your soldier’s action for a turn so that they can instead automatically fire at any enemy which enters or moves within their line of sight. It’s used both for pure caution and to set up elaborate traps, so that an enemy whose cover is removed or who makes a beeline for an apparently vulnerable player soldier ends up getting the Alex Murphy treatment the second he wriggles a toe. Learn Overwatch. Love Overwatch. More on that shortly, but first: don’t use Overwatch too much.
There are two main downsides to Overwatch: the first is that, most of the time, shots taken this way have a reduced chance to hit compared to a standard in-turn short. It’s tempting to presume that Overwatch is a get out of jail free card when all your soldiers are in cover and you think the aliens will thus have to come to you, but you might be squandering perfectly good in-turn shots that way. Also bear in mind that, bar a late Specialist skill unlock, Overwatch only triggers on movement, not on action: so an alien who stubbornly refuses to leave the pillar he’s hiding behind will be free to fire hot plasma or lob a grenade at you.
The second downside is that Overwatch only allows standard shots. Before you set all six soldiers into Overwatch, consider whether any of them have any other abilities that would have a more beneficial effect.
A Grenadier’s bomb blast might not be sufficient to totally murder anything, for instance, but it could take enough hit points off two, three or more enemies that, when the rest of the squad’s Overwatch does trigger, they kill rather than merely wound your foes. A Specialist equipped with a Mindspike could go insta-kill an Advent Shield Bearer with it, which means the blighter won’t be able to clad his chums with extra protection. A Sharpshooter who’s gone down the pistols side of the tech tree will get to take two shots once he’s ranked up a couple of times. A Mimic beacon will keep enemy fire off vulnerable soldiers’ backs for a turn. All sorts, basically: Overwatch is great, but it can be a huge, huge waste of enemy-management opportunities.
Cover is not optional
This should be obvious, but I’m including it just in case. Cover isn’t just a minor boost to defensive odds: it’s very often the difference between life and death. Leave a soldier out in the open and not only will the enemy be more likely to hit him, but every foe in sight will make him their number one target because of that. He’s dead, basically. Unless you have the Ranger’s Untouchable skill, throw an aim-confusing smoke grenade around him or use the Specialist’s quietly vital Aid defence-boost skill.
Later on, a psi-operative’s Inspire skill can also give an extra action point to someone left standing in the open – plan this in advance and you can have someone run to an exposed front line to take an easy shot, then be psionically granted an extra action so he can get the hell out of dodge.
The best time to use Overwatch
Like I say, Overwatch is the bedrock of any XCOM strategy, but it has its shortcomings. However, it loses one of those - the reduced chance to hit - if you're firing from Concealment. (Concealment being the stealthed mode you begin most missions). The game does give you a short ambush-from-concealment tutorial near the start, so I won't repeat that now, but I don't think it says anywhere other than on a loading screen tip that you don't have the aim handicap this way. Use it; especially in combination with high-ranking skills, you can end up with the most deliciously deadly traps. However, keep the following in mind:
Don't spring your Concealment ambush too soon
It's very, very tempting to set up an Overwatch trap on the first enemies you see on a map begun with your guys in Concealment. You thirst for blood, yes, but it's also a frightening concept to leave any foes alive: they could come back to bite you any time. However, once the trap is sprung, your Concealment's over for the rest of the mission (bar some Ranger abilities and hack rewards) and you'll never get that sweet, sweet unpenalised Overwatch again. So, see if you can make it to the second pack of enemies before you unleash hell - primarily because that way you can start combat a little closer to your objective rather than have to battle the whole way to it.
A bit later in the game, your squad should become capable of dealing with more than one pack of enemies at a time too, so it pays to try and ensnare more foes into that initial trap rather than waste the opportunity on just a couple of basic grunts.
The first group of enemies you spot usually patrols the map, so if you keep out of sight there is a reasonable chance they'll wander out of mutual sight range. However, they might instead wander closer to where your guys are crouching, so make sure they're sufficiently sheltered - if flanks are exposed they'll be seen and Concealment is over for everyone.
On page two, XCOM's most overpowered gadget, tactics for taking down their most dangerous foes, some base-building tips and how to handle those timers.
Perhaps the most stressful tweak to the XCOM formula in this sequel is that there are far more missions with timers – i.e. if you fail to complete the objective in a set number of turns, you fail. In some cases, if you don’t get some of your team to the evac point before that timer expires, they’ll get left behind. Timers are bad news, basically – but they can be managed. For instance:
- On VIP retrieval maps, move Sharpshooters along an outside edge of the map, creeping closer to the evac point but retaining a line of sight to the core of the map so they can support the rest of the squad as they move up the middle. This way, you don’t end up with a situation where the bulk of your squad are at the evac point but your snipers are stuck a three-turn run away and wind up left behind.
- On timed maps where you have to retrieve an object (e.g. train cargo) or hack a terminal, Specialists can make all the difference. If one of your units has line of sight to the objective, the Specialist can send their Gremlin in to access it remotely, thus saving you a run (or, more pertinently, from winding up in a situation where, if you do run, that soldier’s turn will end and they won’t be able to access the object until the next one, which may well be too late) and reducing the risk of uncovering a new pack of enemies when you do.
- Again, Specialists are your besties. Make sure you’ve taken one down the hacking rather than healing tree, as they can then disable (or, if they’re good enough, take temporary control of) turrets. While clearly this helps in terms of having one less enemy shooting at you, the real win is to do it early, while your squad’s still in concealment, as it disables the turret’s optics too – meaning you can move closer to your objective without being spotted. (You can do this with MEC units too, but unless the MEC is all alone doing so will let the enemy know you’re on the scene.)
- Use roofs! Roofs are good. You get a longer line of sight, you're harder to hit, there can be fewer obstacles to cross once you're up there and some Sharpshooter builds get a bonus action if they kill an enemy at a lower elevation.
- Mindspikes and Ranger swords can be used after two moves, so long as you start the whole move by clicking Mindspike or Slash on an enemy. This means you can travel a long distance and potentially get a kill: though make sure you have a good idea what position you’ll end up standing in. Ideally, do this in tandem with a Sharpshooter who has the Squadsight ability (and possibly is in Overwatch) so that they can take a crack at any new enemy your run ends up exposing.
- A Grenadier (or standard grenade) thrown at the side of a building that your objective is inside can bring down a wall so nearby soldiers can see inside without having to actually go into the lion’s den. You can pair this with Overwatch so that the aliens exposed when the wall comes down take a couple of hits when their initial scatter animation triggers.
The Mimic Beacon is OP
The Mimic Beacon, which can be built after you research a Faceless Autopsy, is the single greatest weapon in XCOM’s arsenal, and it’s one you can get pretty early on, after the first Retaliation mission. What it does is spawn an static hologram of an XCOM soldier onto the battlefield for one turn, which for some reason the aliens all decide is a real person even though it's blue, flickery and see-through.
But never mind: simply by dint of being an extra target on the battlefield it splits the aliens’ guns’ vote, but the reason it might just be overpowered is that it also becomes their number one target. Not all aliens will zero in on it (for instance, a Codex won’t pass up the chance to EMP-blast a clustered XCOM group) but by and large it'll take all the heat, at least until the end of the turn or all its hitpoints are zapped away - whichever happens first.
If you’re left in a tricky spot – e.g. a unit out of cover or there are more enemies on the field at the end of your turn than you could possibly survive – there’s a reasonable chance the Mimic will buy you another turn’s play. It’s particularly useful once the really big hitters, such as Sectopods and Gatekeepers arrive: often those guys can’t be taken down in a single turn, and their weapons are capable of insta-kills. Let the Mimic take the hit for you. Don’t go into battle with fewer than two of them equipped.
Don’t Underestimate Vipers
The fast-but-frail Snakewomen are a relatively early foe, but they’re no less deadly in the late game. It’s the tongues, you see. The Vipers can cross great distances, then use their extending gobs to pull an XCOM soldier a long way from his pack, do damage over time and prevent him from any activity until the Viper is harmed. If there’s another Viper on the scene, it’ll likely spit poison at the bound XCOMmer which means double damage over time and a potential death if you fail to help them out during the next turn.
This is another good reason to a) not leave anyone too far from an ally and b) always have someone long-range in Overwatch.
Beware The Shieldbearer
If an Advent Shieldbearer appears on the scene, consider dropping everything else you’re doing to take him out in the first turn. He will almost certainly give any nearby comrades four additional hit points come his turn, and that usually means each one requires at least one additional hit to kill.
Trouble is, Shieldbearers are pretty damn well protected themselves. One effective trick I’ve found for disposing of them quickly is to run a Specialist equipped with a Mindspike right over to them: you do have to face the RNG gauntlet twice (once to land the blow, the second to ‘hack’ the enemy’s brain) but it does mean an insta-kill if it works. Psychics’ Stasis ability is also a good way of keeping a Shieldbearer from doing his thing for a turn, which might buy the time you need to whittle away a more pressing threat.
Don’t Shoot Codexes
Not unless you’re reasonably confident of an outright kill or still have a couple of guys who are accurate at long range still active, anyway. As soon as a Codex takes any damage, it creates a clone of itself, usually some distance away. Granted, both the original and the newbie will have half health as a result, but it means you’re faced with two enemies rather than one, and that means twice the deadly potential come the alien turn.
Each Codex also gets teleportation, which can stymie Overwatch shots, and an EMP blast which unloads the weapons of anyone caught in it, as well as causing a large area-of-effect explosion come the subsequent turn. (So, if some of your guys get affected by that, don’t just reload their weapons so they can take a shot – instead you need to get away from the big purple cloud urgently).
If you’re going to shoot a Codex, do it with a high-damage character like a sniping Sharpshooter or a close-range Ranger – or try and catch it with someone with an ability that lets them fire multiple shots as a single action, as the Clone animation doesn't trigger until they're all done.
Prioritise building the Guerilla Tactics School ASAP
As I said, I don’t want to say too much about the meta-game just yet as I want to have another run through the campaign first, but one thing I have discovered across one and bit playthroughs is that the Guerilla Tactics School is vital. The game will be nagging you about resistance comms and psi-labs, but put those aside until this is up. Two reasons for that: one is that you can expand your squad size to five once one of your units makes Sergeant, and the other is the Lightning Strike purchase that grants your entire team 3 extra movement squares for the first two turns of a mission (as long as they’re in Concealment). This can make all the distance in a timed mission: essentially, everyone gets one extra move across the space of those first two turns, which can get you closer to your objective before all hell breaks loose.
And also maybe the Advanced Warfare Center
I’m a little less forceful about building this one, as it’s costly and will set back some fairly vital early-game setup, but it’s still prudent to get it finished fairly soon. Its main use is to grant soldiers bonus abilities as they rank up, but it’s important to understand exactly how this works.
Once the building goes up, every current soldier is invisibly tagged with one extra skill from a different class to their own. However, this new skill is also attached to a random, unknown rank, and it will only be unlocked when the soldier in question attains that particular rank. But it doesn’t work retroactively: so if, for instance, one of your soldiers is already a Major when the AWC is built but it silently decides that they would receive their bonus skill when they became the earlier Sergeant rank, they will never be given that unlock. The ship has sailed.
What this boils down to is that the higher-ranking your soldiers are, the less likely they are to get new skills. And these are match-changing skills, such as a Grenadier gaining the Untouchable perk (which means she’s invulnerable during the alien’s turn so long as she got a kill in her own one) or a Sniper getting a second Overwatch shot if the first one gets a kill. A high-ranking squad where everyone’s got a bonus skill is true super-squad.
Hence, the sooner the AWC goes up, the more of your soldiers are going to get their bonus skills – presuming they live long enough.
There's a meme going around on Twitter, a picture of an XCOM soldier with a shotgun touching right up against a Sectoid's nose, and the to-hit chance is only something like 68%. Silly old XCOM with its random numbers, it doesn't make sense, the devs are stupid etc etc. Admittedly, XCOM 2 is guilty of a certain presentational stumble here, its animation and UI not making it at all clear that the situation is not, in fact, your guys moving and shooting in real-time while the aliens are completely frozen, but it's still very, very important to think about the abstraction that's going on if you're to survive a campaign.
The Sectoid isn't moving in the game, no, but in the game's concept - a real-time battlefield - it will be ducking and diving, trying to smack that gun out the way, trying to pull out the soldier's eyeballs, and everything you would expect a space monster to do when you run right up to it. The soldier's hit chance does not jump to 100% just because he's stood right next to it; that's based as much on his own aim stats as it is the distance; i.e. how good is he at fighting?
Yes, there's a million things wrong with how XCOM presents this kind of information, and in some respects it can appear to wildly contradict itself, but understanding that running right up next to an enemy is also running right into danger is very important. If you are going to get that close, do it with a Ranger and their big old swords. And even then, make sure the enemy in question isn't going to swipe your ranger aside with a crushing counterattack. Mutons, I'm looking at you.
A 90%+ shot is not a guaranteed hit
There's still a one in ten chance that you will miss. That's pretty high, really. At some point, you will almost certainly become angry when a soldier screws up an apparently sure thing, and will decide that the game must be cheating. Well, it does indeed seem that some behind the scenes skullduggery goes on, though it works in the player's favour as well as against it, but something else is happening too.
Because you are more likely to take shots with good odds than shots with bad odds, more of your overall shots will be those with good odds. Thus, you are increasing the odds of the numbers not being in your favour on a high-percentage shot. It is as or even more likely you will miss on any given 90% shot than on a 27% one, because you are taking far more 90% shots.
So, once again: the advice is don't go alone, and think hard about the order your soldiers take their actions in, because there is a real chance that your 92% shot taken as the final action of your turn will miss.
Good luck, Commander.
For more on XCOM 2, visit our XCOM 2 guide hub.