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