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Greetings, Commander. The aliens continue their stranglehold over our planet. You and the brave men and women fighting for XCOM are our secret weapon. Many soldiers died bringing you these invaluable tips, so that others may live. Keep fighting and we’ll win this war. Good luck, Commander.
Know the Timing on the Avatar Project
The only way you can really lose XCOM 2 is if the Avatar Project is completed. However even when the bar fills up, a 20-day countdown timer begins. You get a bit of a grace period to immediately launch an assault on the nearest enemy base. Make sure you’ve been making the right contacts and always have a base to infiltrate when the counter gets too high.
XCOM 2 is pretty forgiving when it comes to building your facilities. Prioritizing which to build first is largely a matter of preference. Build that Guerrilla Tactics School ASAP, as it provides the upgrades needed to field additional soldiers. Stick it in one of the top corners. You’ll also want your Workshop somewhere in the middle. It’s the only building that cares about adjacency, and you can staff an engineer to then staff nearby buildings via remote gremlins.