Here is the full list of all 31 Stop Dead achievements.
Die to a ninja oneshot after they teleport behind you.
Skip a story level by entering the win zone before the dialogue finishes.
Get to the top of The Elevator.
Defeat the Engineer.
Die to the Motivator for the first time.
Kill an advertisement bot.
Shoot all 3 piggy banks in Line of Sight.
Get a kill with a pizza.
Defeat the Fire Mech.
Die to your own explosive after triggering it.
Kill a Rocket Brute with their own missile.
Submit 3 ghosts. Unlocks the "Baseball Caps" hat.
Chain 50 perfect jumps in a row. Unlocks the "Kitten" hat.
Defeat a target with a Zweihander. Unlocks the "Sunny Helm" hat.
Land a critikill with every shot from a revolver. Unlocks the "YEEHAAAAAAAAAAAAAAAAAAAAAAWW" Hat.
Kill your first target. Unlocks the "Pompadour" Hat.
Play during christmas. Or cheat it. We don't care. Unlocks the "Festive" hat.
Submit a run 3 or more minutes in length. Unlocks the "Slowpoke" hat.
Kill 3 enemies in one Laser Sword teleport. Unlocks the "Straw Hat."
Get an S+ on any level. Unlocks the "Distinguished" hat.
Submit your first leaderboard score. Unlocks Ghost Customization.
Pick up 25 different items. Unlocks the Itemdex.