In XCOM 2, the Avenger is a large alien vessel which essentially serves the purpose of being the Base of Operations. At the start of the game, you will come across different sections of the Avenger marked in ‘green’.
XCOM 2 Avenger Facility Upgrades Build Order
Avenger in XCOM 2 is basically made up of destroyed facilities which can be rebuilt as you go on and unlock them. This guide details the optimal build order of these Avenger Facilities.
Avenger Facilities Optimal Build Order
After you begin the game, your first building should either be the Advanced Warfare Center or the Guerilla Tactics School. The following section details the positive and negative points of both:
Advanced Warfare Center
One of the reasons that you should build this early is to get those early random promotions and render them tough during the late game. In addition to this, you also get the slot to place the engineer in order to double up the recovery time of soldiers is pretty good.
Coming to negative sides, the chances of random promotions is incredibly low and so it is risk and reward type of situation. In addition to this, you miss out on the opportunity of training at the Guerilla Tactics School.
Guerilla Tactics School
This basically allows you to train your rookies as early as possible and not only get free experience, but also field all starting missions without worrying about rookies.
In addition to this, you do not have to reserve your engineer and use him for construction and clearing out other rooms. On the down side, you miss out on all the special promotions and fast recovery time of wounded soldiers acquired from the Advanced Warfare Center.
After getting Guerilla Tactics School and the Advanced Warfare Center out of the way, you will need to build a Power Relay. As for its placement, you are free to do as you prefer except the center-second row as it is the optimal position for the Workshop.
Speaking of the Workshop, this is the next building that you need to build. As I mentioned above, the optimal positioning for the Workshop is center-second row in order to acquire most mileage out of Gremlin drones.
In addition to this, you should also prioritize on upgrading the Workshop in order to get the 2nd engineer slot as soon as possible. The reason for this is more constructions, more clearing out the rooms, more engineer bonuses, more supplies, and of course; the Gremlin drones.
The sole reason why Proving Grounds is so pushed out in the order despite all those gadgets, grenades, and other cool things is rarity of Elerium Cores.
In addition to this, since most of the projects acquired from the Proving Grounds only become applicable after you have researched some advanced technology, there is really no need to build it first.
Moreover, most of the early missions on the game can be completed just fine without projects from the Proving Grounds.
Once you are done with all those facilities mentioned above, you can go for anything you want. However, if you decide to go for the Shadow Chamber; do not place it adjacent to the Workshop as there are no available engineer slots.
It is more fitting that you go for another Power Relay instead of the Shadow Chamber as the 6th facility and try to place it inside the Power Coil room which will provide your Power Relay with an additional +10 power.
Building the Resistance Comms
Your next facility needs to be the Resistance Comms which will allow you to drastically enhance your reach around the in-game world.
Doing so will essentially allow you to develop more resistance connections, sabotage enemy facilities, and prolong the Avatar Project. Not only this, but it will also enhance your income via monthly supply drop.
This guide is currently a work-in-progress. We will update it with more information.