Here is the full list of all 18 Defense: Abominations achievements.
Unlock your First Turret
Unlock the Rifle
Unlock a Second Turret
Unlock the Fire Thrower Turret
Unlock the Gatling Turret
Double Your HP
Unlock the Rocket Launcher
Unlock The Shotgun
Kill a Velociraptor
Kill a Baby Spinosaurus
Kill a Zombie
Kill a Big Reptile Mutant
Kill a Mutant Dog
Kill a Masked Mutant
Kill a Fighter Mutant
Kill 100 Abominations in a Row
Kill 1000 Abominations in a Row
Reach Level 9