Here is the full list of all 15 Infiltraliens achievements.
Beat level 1
Go through the ventilation shaft in level 3
Beat level 2
Beat level 3
Beat level 4
Beat level 5
Jump through a window of the bean shack
Make 4 guards dance at once
Throw 10 items
Throw 50 items
Throw 100 items
Explode a TNT while it's in your hands
Use two Fire Extinguishers at the same time
Destroy 20 containment tanks
Thrown 20 barrels