Part 28

Learn how to tackle the Alien Base Assault mission in XCOM: Enemy Unknown. This guide covers acquisition, objectives, enemy types, and tactics for success.

Alright, so you've crafted the Skeleton Key and you're ready to take the fight to the aliens. This is it – the Alien Base Assault mission. It's a big one, and it's essential for your progress in XCOM: Enemy Unknown. Let's get you prepped. ## Acquisition This mission pops up after you've successfully crafted the Skeleton Key using an Outsider Shard. Once you have it, you can initiate the mission anytime from Mission Control. Just remember what Central Officer Bradford says: "We've only got one chance to make this work though, so let's make sure we do it right." ## Mission Brief When you get the mission brief, pay attention: "Use extreme caution; analysis indicates the presence of a large combined enemy contingent. This mission cannot be aborted." That's right, no turning back once you're in. You're committed. ## Mission Objectives Your main goals are pretty straightforward: * Penetrate the base's defenses * Neutralize all invader forces * Identify and capture the base commander, if possible That last one is super important for Psionics research later on. ## Mission Site The Alien Base itself can have a couple of layouts, usually an L-shape or one without. They're mostly corridors with guardrails for cover. Keep an eye on the elevation changes; higher ground can give you a nice Aim and Defense advantage. Some areas have open spaces with good cover, perfect for your shotgun-wielding Assault soldiers. ## Enemy Types This mission throws a lot at you. Depending on how far into the game you are, you could face almost every alien type except Ethereals and Outsiders. The number of enemies varies by difficulty: 22 on Easy, Normal, and Classic, and 28 on Impossible. ## Tactics Advance carefully, using cover and Overwatch whenever possible. Aliens love to hide behind doors, so be ready to breach. The multi-level design can be tricky, as it hides enemy patrols, but also offers those sweet vantage points. Your main challenge will be the final encounter with a Sectoid Commander – your first time seeing one! ### Capturing Sectoid Commander This is critical! You *need* to capture the Sectoid Commander alive using an Arc Thrower. This allows you to interrogate it back at base, which unlocks vital Psionics research. Don't kill it if you can help it!