Halo: Campaign Evolved's "Assault on the Control Room" mission includes three collectible skulls and one terminal for players to find, continuing the pattern set by other levels in this remake of the original Halo game. The mission is notable as the first time in the series that players get to drive a Scorpion tank, which is also required to reach one of the hidden skulls, adding an extra layer of exploration to the combat-heavy level.

Polygon's guide details each collectible's exact location: the "IWHBYD" skull sits inside an icy wall reachable via the Scorpion's cannon; the "Tangent I" terminal is found on a balcony inside a rock formation after clearing enemies including a cloaked elite; the "Angry" skull rests atop the third of three bridges crossing a valley; and the "Cowbell" skull is tucked beneath a bridge, accessible via a support beam, near an optional achievement for killing an elite before it steals a Banshee.