Chicken KillerG 10

Chicken Killer G10:
Killed 200 plague chickens.

Plague Chickens can be found in the Zombie levels. One Plague Chicken in Wave 1 and two Plague chickens, in every Wave after that. The easiest way to get this achievement is by playing Zombies, in Operation One (Unicorn Lair). Kill all the Plague Chickens up to wave 8 (including the two chickens from wave 7), for a total of 13 Plague Chickens. Then die. Rinse and repeat, until you have killed 200 Plague Chickens and the achievement will pop.