Here is the full list of all 13 Reptilian Rebellion achievements.
Kill the Pop Star, in her sport car
Find the Illuminati Leader in his limousine and send him to hell
Kill 5000 reptilians
Destroy 10 Swat Vehicles
Kill 2500 reptilians
Survive 5 Chem Trails
Collect 10 Bitcoins
Destroy 5 Hell Riders
See an UFO
Kill 500 reptilians in a game with RON
Kill 1000 reptilians
Kill at least 20 reptilians with an Hydrogen bomb
Collect 25 Bitcoins