You forgot one, one for Team Deathmatch:
Spice of life 20 Play a match with every mutator, using only 1 per match.
Play Instant Action matches with every mutator, if you have played deathmatch and used all the mutators 1 per game and you have not got this don't panic as there is 3 more in CTF, Warfare and Duel. When you finish playing a match with the last mutator the achievement will unlock.
Here is a list and and gamemodes you should play them on as to not get confused. Work your way through this list and you will get it. Remember it is only 1 per match.
Kills Slow Time
No Super Pickups
"There are two types of friends, those that help you and those that help you hide the bodies."