Terminal 2 | Forerunner Halo 4 Guide

When you clean the area, go down where you find a second Terminal (screen). Then go to a rock shelf on left or right and go over the balcony (over Terminal) from which enter corridor. On your way you find a lot of ammo and weapons.

On the other side you find a place shown on the screen - it'll be well protected. You can stay in corridor and fire from there. When there is no one left in your range, turn back to corridor, pick up ammo and go inside to kill remaining enemies.