There 2 of those bridge and if there is a brute and grunts are the wrong bridge

where is the cowbell skull?????

if u open your eyes then u might see it

Unlike the ***** answers above, I will tell you how to get the Cowbell Skull.
When you enter the Ark to find the cartographer, you know, after you defeat the Scarab
Tank, and go up the stairs to meet the Arbiter, there should be the hallway sloping
downward with some divided spaces above the doorway. If you use the Grav Lift, you can fly
up into the highest of the spaces and there is the skull. Cowbell makes better explosions.