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