Here is the full list of all 43 Over 9000 Zombies! achievements.
Kill over 1000 crabs!
Get 15,000 damage per second!
No 8th symphony for zombie Sibelius!
The zombie world is independent of our will.
Kill over 1000 zombie eyes!
Vote for Zombie Thomas Jefferson, or don't.
Abused patience turns to fury!
Health is the greatest gift, a close second is BRAINS!
Voted the greatest zombie of all time!
Terror possessed me then!
If only he had the body of a horse...
A jail is an isolated system.
Derail the Waltz of the Undead!
Blood and Flesh can be trusted.
Kill over 1000 zombie dogs!
Decreased Zombotropy.
Kill 9,000+ Zombies!
Quoth the Raven "Nevermore."
Kill over 1000 zombie crows!
Don't call me slow!
You didn't donate your organs...
Your world didn't end!
It didn't taste like chocolate ice cream either...
Not a wimp.
Lots of progress!
You watched the world burn, and survived. It was kind of cool.
Green IS good.
Kill 1000+ Zombies!
You won that race.
Making some progress...
Get 5,000 damage per second!
Construct a turret from scrap metal!
The first day is always the hardest, except in this case, it's the easiest.
Get 10 kills per second!
Kill 90,000+ Zombies!
Kill 900,000+ Zombies!
Construct 100 automated turrets.
Construct 1000 Turrets from random scraps of metal!
Get 30 kills per second!
Collect 100 Power Ups!
Participate in a multiplayer game.
The army of the undead will march at daybreak!
Zombie Napoleon meets his zombie Waterloo!