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