Here is the full list of all 14 Anti Air achievements.
Defenders who joined during the first phase of Early Access
Joining the Anti Air battle gives you the rank of Corporal.
Earn the rank of Major at the end of battle.
Earn the rank of Colonel at the end of battle.
Earn the rank of General at the end of battle.
Earn the rank of Marshal at the end of battle.
Defenders who joined the battle and played during the later phases of Early Access
Battle the Cubicon invasion and shoot down 5000 Cubicons
Unlocked and tapped every stone in a Shooting Range session.
Defeat the Cubicons and complete the campaign mode.
Make it to stage 16 in the Arcade mode.
Unbox a total of 100 crates in the Arcade mode.
Achieving a victory with an accuracy of 64% or more
Unlock and shoot with all different weapons in a single battle.