Here is the full list of all 32 Mop of the Dead achievements.
Collect 1 cleaning product
Collect 5 cleaning product
Collect 20 cleaning product
Collect 100 cleaning product
Collect 1000 cleaning product
Collect 1 key
Collect 10 keys
Collect 50 keys
Collect 500 keys
Revive 1 other player
Revive 10 other players
Revive 25 other players
Revive 50 other players
Revive 100 other players
Reach level 5
Reach level 10
Reach level 25
Reach level 50
Reach level 75
Reach level 100
Win 1 game in any difficulty
Win 10 games in any difficulty
Win 50 games in any difficulty
Win 100 games in any difficulty
Win 1 game in nightmare
Win 5 games in nightmare
Win 20 games in nightmare
Win 50 games in nightmare
Win 100 games in nightmare
Getting killed 1 time
Getting killed 10 times
Getting killed 50 times