Here is the full list of all 12 Warhammer 40,000: Kill Team achievements.
Earn a gold Aquila in every survival challenge
Defeat the Warboss!
Unlock all weapons and ability upgrades
Kill 5000 enemies in total
Achieve a "Bloodbath" Kill streak
Complete a mission in co-op mode
Complete a mission without using melee
Complete a mission without dying
Use a special move
Find all the collectables
Get over 50 kills with each weapon type
Play through each mission with two different Space Marines