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