No missable achievements (plus 42 unknown)
Sign in with Steam or Xbox to track your progress, and:
Fully upgrade any weapon.
Play the game for 30 minutes in battles.
Don't use medkits for 5 levels in a row.
kill 15 enemies in 2 seconds with any gun.
Kill 400 by setting them against the others.
Resurrect.
Fully upgrade any turret.
Buy 5 any weapons in the store.
Buy any special ability in the store.
Don't use turrets while 10 battles.
Play the game for 15 minutes in cooperative mode.
Use any special ability 100 times.
Kill 5000 any enemies.
Kill 2000 enemies with auto rifle.
Kill 900 by setting them against the others.
Kill 10000 any enemies.
Kill 4000 enemies with auto rifle.
Complete the game.
Kill 2000 enemies with a shotgun.
Complete 8 levels with 3 stars.
Complete the N'Aliens campaign.
Set up any 3rd level turret during battle.
Kill 4000 enemies with turrets.
Complete the game with Warrior.
Complete the game with Mechanic.
Kill 2000 enemies with a grenade launcher.
Kill 2000 enemies with Electric rifles.
Kill 4000 enemies with a shotgun.
Kill 20000 any enemies.
Complete 8 battles on HELL difficulty.
Complete all levels in cooperative mode.
Kill 2000 enemies with a sniper rifle.
Kill 4000 enemies with a grenade launcher.
Collect all samples of matter hidden in the levels.
Complete all levels on HARD difficulty.
Kill 4000 enemies with Electric rifles.
Destroy 1200 crystals blocking the way.
Kill 4000 enemies with a sniper rifle.
Get three stars for all the levels in the main campaign.
Complete all levels on HELL difficulty.
Complete the game as Medic.