Here is the full list of all 15 Zombie Bloxx achievements.
Unlock all epic characters
Use revive 50 times
Play the game for 5 consecutive days
Try out 3 characters in special offer
Complete 5 daily missions
Hit a max combo of 25
Survive for 20 seconds without killing a zombie
Die under 5 seconds
Get 1000 kills in one session
Play 100 games with a single character
Claim all 28 daily rewards
Unlock all common characters
Unlock all rare characters
Upgrade any character to max level
Complete all quests