The Citadel is the Alien version of the rebellion Bridge, and most likely runs the entire Alien Base making it contain the most percentage, stats, and intel in the base. It is however very armored and is well guarded by many Alien Combat Modules and Alien Squadron Modules making it hard to attack.
In Infected and Heavy Infected Outposts, it also has a built-in Alien Squadron Module that is designed to repel squadrons. In Heavy Outposts, the Citadel also launches 2 Elite Gladiator Swarms identical to those of the Squadron Modules.
When destroyed, it deals a lot of collateral damage, making it a priority target as taking it out first will decimate any nearby modules.
It is advised to not target the Citadel first thing when attacking an alien base as you will be bombarded in heavy fire, often leaving a hull or 2 destroyed. Players should instead rim a part of the base and then rush in through the opening, or simply rim the outer edges of the base and then go in. Don't worry as the Citadel won't fire on you if you stay far enough away.
When finally attacking the Citadel use the collateral as an advantage. Take out a few Alien Energy Capacitors surrounding it and then attack the Citadel, the collateral damage will wipe the rest of the turrets off.
When dealing with Heavy Outposts, shield-switching against the beams is almost impossible unless you have good squadron defense such as Suppressors.
- The Alien Citadel seems to look like the inside of an Alien Hive however it is much bigger than in the photo.