Catch Skull
Catch Skull Effect: Your Enemies throw LOTS of grenades.
Catch Skull Location:
The “Catch Skull” can be found on the fourth level, in the first area where you need to destroy the Wraith Tanks. When you enter this area, do not eliminate the Wraith Tanks (The skull appears when the tanks appear, and disappears when the tanks are destroyed). The Skull is located on top of the circular building next to the Anti-Air Tank. You can access the roof using a grenade jump, or jumping on the back of a hog.