Here is the full list of all 50 room13 achievements.
Slaughter 50,000 of the Dead
Slaughter 25,000 of the Dead
Slaughter 22,000 of the Dead
Slaughter 20,000 of the Dead
Slaughter 18,000 of the Dead
Slaughter 17,000 of the Dead
Slaughter 14,000 of the Dead
Die 1,000 Deaths
Slaughter 13,000 of the Dead
Slaughter 11,000 of the Dead
Slaughter 10,000 of the Dead
Slaughter 9,000 of the Dead
Slaughter 7,500 of the Dead
Survive 35 Rounds in a Single Game
Survive 30 Rounds in your Career
Survive 25 Rounds in a Single Game
Slaughter 6,000 of the Dead
Survive 110 Rounds in your Career
Survive 100 Rounds in your Career
Slaughter 5,500 of the Dead
Survive 80 Rounds in your Career
Survive 90 Rounds in your Career
Survive 20 Rounds in a Single Game
Survive 15 Rounds in a Single Game
Survive 10 Rounds in a Single Game
Survive 70 Rounds in your Career
Slaughter 4,000 of the Dead
Survive 60 Rounds in your Career
Slaughter 3,500 of the Dead
Survive 50 Rounds in your Career
Slaughter 3,000 of the Dead
Survive 40 Rounds in your Career
Survive 30 Rounds in a Single Game
Slaughter 2,250 of the Dead
Slaughter 1,700 of the Dead
Survive 20 Rounds in your Career
Slaughter 1,300 of the Dead
Slaughter 1,000 of the Dead
Slaughter 750 of the Dead
Survive 10 Rounds in your Career
Slaughter 500 of the Dead
Survive 5 Rounds in your Career
Slaughter 300 of the Dead
Survive 2 Rounds in a Single Game
Slaughter 150 of the Dead
Just Kill Something
Use the Machine Gun Barrel
Use the Pellet Gun Reciever
Use the Level 0 Stock
Use the Starter Magazine