This page details where to find all the collectibles for the Foundation campaign mission, including UNSC Audio Log, Cowbell Skull, and Banished Audio Log.
Foundation Collectibles - Cowbell Skull
After the scene during which you find the Weapon, the platform you’re on will rise and take you to a different part of the complex. A collectible in the form of the Cowbell Skull can be found here, so don’t run through too quickly. Head up the stairs in front of you and go through the two automatic doors highlighted in blue. You’ll encounter a few Grunts in this next cavernous room, and the Weapon will note that there’s something up ahead, hinting at the nearby skull.
Once you’ve dealt with the Grunts here, look up and to your right, using AI Scan. You’ll see the skull highlighted in yellow on top of one of the structures. To reach it, you’ll need to use your Grappleshot at least twice, as shown in the gif below:
Foundation Collectibles - Banished Audio Log
Once you’ve acquired and activated the Weapon, use your AI Scan to highlight the way, as you reach yet another cavernous room with a crucible in front of you. Interact with the crucible to raise the bridge, then head over it, killing the Grunts which appear as you go. This will lead to an area with even more Grunts, Brutes, and Jackals, so be ready to fight them. There’s a plasma cannon at the end of this room, so spare some ammunition in a gun with more precise fire so that you can take it out, or just throw grenades at it if necessary. There’s plenty of structures to take cover behind as you finish off others in the area. After defeating all the enemies in this room, you’ll find a Banished audio log beside the door located behind the plasma cannon.
Once you’ve acquired the Banished audio log, continue through the hallways until you reach a room with a sniper and an offline gravity lift. To activate the gravity lift, use Grappleshot to reach the platform where the sniper was. You’ll find a power seed up here which you can use to power the crucible below. When you’re up the gravity lift, head through the hallways until you reach a room with a dead Spartan. Investigate the body to acquire a Mjolnir Suit Upgrade for your shield. You’ll need to power this with a Spartan core, something which you’ll come across soon enough. Once you’re done investigating the Spartan, you’ll enter another room with more Grunts, Brutes, and Jackals. Take them out by focusing fire on the snipers on both sides of the room at the upper levels.
Foundation Collectibles - UNSC Audio Log
After you’ve killed all the enemies in the room with the elevator, head to the end of it to find a control terminal which is used to call down the nearby elevator. Interact with it to confirm that it requires a power seed, which you can find by following the objective marker to a large room with a long walkway into the centre. The Weapon will comment on the genetic repositories in this room. At the end of the walkway you’ll find the power seed, and a UNSC audio log to the left of it.