Unlike other adaptations of Ridley Scott’s classic horror series, Aliens: Dark Descent doesn’t put you into the boots of a single survivor but gives you command of a whole squad of marines to fight the Xenomorphs. By pulling the focus back, survival becomes less about any one soldier’s skills and more how you manage the positioning and abilities of your unit against an acid-blood-spattered uprising.

While similar to turn-based tactics games like XCOM 2 and Xenonauts 2, Aliens: Dark Descent has unusual systems you’ll need to master. You can fumble your way through the opening levels, but by the mid-game you may need a guide to make sure you’re paying attention in the right places. It's easy to make mistakes that will bite you hard towards the end of your campaign.

Leaning into the impact of slogging it out with such a terrifying foe, Aliens: Dark Descent sees your soldiers deal with limited resources and the challenge of redeploying in the same colonies for multiple days of fighting—and suffer from the accumulating trauma of battle. Responding to this attrition is the key to victory.

Don’t stress about stress

Every moment your marines are in combat, every second they are hunted, and every time they take a hit from an alien, they receive Stress damage. When Stress hits 100, they receive a Stress Effect—such as Shaking, which reduces their accuracy—and their Stress Level increases. Starting at Relaxed, Marines become Anxious, Panicked, and finally, Terrified. When your soldiers return to the ship, that Stress Level is converted into Trauma Points, one point for each new level, so a Terrified marine receives three points. When a soldier first hits three Trauma Points, they then develop a condition—such as Hypochondriac, which means they will gain additional Stress for every second they don’t have a Medical Supplies.

Trauma is one of Aliens: Dark Descent’s headline features, reflecting the mental toll your marines undergo while battling Xenomorphs in gloomy corridors, but that doesn't mean you should let it lead your decisions.

Stress Effects and Trauma Conditions sound scary, but remember that they're fixable. Hole your marines up in a room, weld the doors shut, and your troops can get some much-needed rest, sending their Stress down a level, even relieving them of a Stress Effect. Also, it’s not in the tutorial, but you can use Medical Supplies to heal Stress instead of wounds—when you bring up a soldier’s action bar, simply select the pill icon instead of the Medical Supplies icon. And later in the campaign, you unlock psychiatric treatment that lets you heal Trauma Points, healing your marines of Trauma Conditions.

It’s easy to stress too much about Stress. Yes, Stress Effects can see your marines’ accuracy drop or your Action Point pool decrease, but they will still behave as competent soldiers in combat. Use cover, Sentry Guns, and chokepoints well and even a panicking marine will down many Xenos.

When to withdraw

Finding the sweet spot for when you should retreat is critical to Aliens: Dark Descent. The longer a mission lasts, the more dangerous things become—your marines take damage, their fear will builds, your resources get low, and the number and strength of the enemy Xenos increases. An easy way to short-circuit this challenge is to head back to your base, resetting the alien aggression level. However, you can only deploy once per day and each day that passes increases the planet-wide number of aliens, meaning that redeploying too often can make the entire game more challenging long-term.

Don't decide when to retreat based on how well you're doing, but on how much experience your marines have earned. Your standard recruit isn’t effective in the late-game. You need the more powerful weaponry that high-rank marines can carry and the skills that come with leveling up. You also need your entire roster to be effective in battle. Given marines have to rest and heal up between missions, you don't want only a few of them to get all the experience.

Your soldiers don’t gain experience killing standard aliens. They get it for completing objectives, defeating boss-character Xenomorphs, and putting down a Massive Onslaught. If you don’t spread the XP around, you can leave your less-used marines with few ways to level up and become useful. After you’ve built a training facility on the Otago, your marines gain experience every day, and you can put marines in for intensive training that sees them level up even faster. Still, the quickest way to level up a marine is by putting them in the field. Training is helpful, but it doesn’t change the need to rotate your soldiers into battle.

All this to say that when all of your deployed marines have leveled up once, you should strongly consider extracting. Promote your marines, apply their skill points, get them healing in the med bay and psychiatric unit, and give some other soldiers a chance in the field. You will feel the benefits of a well-trained barracks in the late game, and if any of your troops are KIA, it won’t leave as large a hole in your roster.

Watch your ammo

The number you should keep a closer eye on than Stress is your Ammo—especially as one of Aliens: Dark Descent’s significant features works against you here. 

You usually return to mission areas multiple times in Aliens: Dark Descent before you complete all your objectives. While enemies respawn between trips, many of your actions in the environment persist. Doors you welded stay shut, terminals you hacked stay hacked, and (most importantly) containers you looted stay looted. Whereas you can only hold a limited number of Tools (for repairing and welding) and Medical Supplies, there’s no limit to ammunition—meaning it’s entirely possible to steal every Ammo box in a level. This can be a real problem as, unlike the other resources, you can’t bring extra Ammo into a mission.

If you let your kleptomaniac inclinations run riot, it can harm you. Let's say your squad carves a successful path through the Xenomorphs on your first run at a level. You open every room, loot every container you can, and hoover up all the available Ammo before returning to your ship to upgrade your squad. When you return to the ship, your starting ammunition resets to the standard four clips. If you later have to backtrack through those same areas you’ve previously explored, there won’t be any new ammo to collect—but there will be lots of enemies. Four spare clips don’t go very far when spread across four marines fighting hundreds of aliens.

A good rule of thumb is to avoid picking up Ammo if your reserves are in double digits. If you start running short and don’t plan on returning to base, then go back and pick up some of the crates you passed by. Easing back on your greediest tendencies can save you from a much more brutal fight in the future.

Be wary of the bugs

While the bulk of this guide addresses getting the most out of Aliens: Dark Descent’s features, this real-time tactics game also has a couple of hefty bugs—and not just the acid-blood-filled kind. It may be helpful to know the workarounds.

A common issue that will absolutely sap your Ammo reserves is using suppressing fire against enemies in cover. The first human foes you encounter are all melee soldiers, so much like when facing Xenomorphs, you can hunker down and order your marines to slow the charging enemies with a barrage of suppressing fire. Anyone caught in the hail of bullets will fall to a crawling pace, giving you ample time to cut them to ribbons. 

However, when you meet firearm-toting cultists, they often take cover behind barrels and low walls. If you use suppressing fire against them, your targets will duck down and won’t come up again until you stop firing—which, with suppressing fire, doesn’t happen. Your soldiers will empty their clips against a target they’ve no hope of hitting, and then reload and empty that clip, too. It’s much better to cancel the order and hit enemies in cover with a grenade, or to let your soldiers' regular firing pattern do the job.

Another bug even more painful than a Chestburster is the endless Massive Onslaught. While the name sounds exciting, it’s game-breaking. As you get deep into Aliens: Dark Descent’s campaign, you’ll encounter Massive Onslaughts—moments when a wave of enemies spawns into the level and charges you down with little warning, forcing you to create a defensive position before you're overrun. Occasionally, those Onslaughts never end, and because you can’t save, extract from the level, or complete any objectives when under attack, you can’t progress either.

The bug happens when an enemy in the onslaught gets stuck in the level geometry, preventing them from reaching you and you from killing it. Because one wave member is left, the onslaught can’t end, and the game state can’t return to regular business. No matter how many enemies you kill, you can’t fix this bug, so don’t try. If the Massive Onslaught state continues long after you’ve killed the incoming wave, cut your losses and load your last save game. You can save yourself a lot of wasted time.

While there isn’t a single cause for the Massive Onslaught bug, it can happen when enemies crowd around destroyed sentry turrets. Repair and pick up your abandoned tech whenever you can.

Aliens: Dark Descent is available on the Epic Games Store.