Here is the full list of all 14 Three Dead Zed achievements.
Took 5 dangerous paths out.
Kill 100 Civilians
Well...not quite yet, but you're looking good!
Beat the game. Unlocked Challenge levels.
Found a secret room. Shhh.
Yep - That's a cat with a tinfoil hat.
You found a secret message.
Your escape begins here. (Start office 1)
Found all secret messages
Found all Potato Boys.
Died 100 times
Died less than 30 times completing the game
Beat the game under an hour
Complete challenge stages in under 45 minutes