After they are dealt with, look to the right of the way you came in, where a large ravine is. The Skull can be found in the rafters of this area and will need a grapple hook to access. Once you climb your way up there, the Skull collectible can be picked up.
The upper ledge has a plasma turret attached, and the grunts will gleefully use it against you. Kill that platform of its grunts and move towards the hallway sentence at the end of the level you’re on. On the left of the hallway entrance, you’ll find the log glowing orange. Find these Halo Infinite Foundation collectibles as you fight your way through the fragments of Zeta Halo to reach the surface. Doing so will give you a bit more background information for the events immediately preceding Halo Infinite’s campaign, so any lore enthusiasts should keep an eye out. Here are all the locations for the Halo Infinite collectibles in the Foundation mission.
Ride the elevator up after the cutscene, and follow the critical path forward through the next door and hallway. At the end of the hallway, go through the door and then left through the corridor. The first collectible that players will encounter in the Foundation is Halo Infinite’s Cowbell Skull, and it is the most difficult one to access. To reach it, players should locate the weapon and then ride the lift.
Hang out on the platform and listen to the various fragments of memories as Chief and The Weapon are moved through the Foundation. There’s nothing to find in these areas, so just enjoy the story and proceed through the room at the top of the landing. The weapon Master Chief needed to retrieve wasn’t bill and hillary clinton divorcing a gun of any sort, but an AI codenamed The Weapon. Upon interacting with the Chief she states she’s been there for six months, meaning the Chief survived alone in space for quite a long time. She recounts the mission details but is stumped at some of Chief’s questions regarding Cortana’s deletion.
Then, towards the end, where you reach a large room where you can form a light bridge then turn to the left. Grapple up the columns and you can access a room above. To reach these side rooms, you must head to the start and end of the room respectively, then grapple across the supports between them.
This skull will speed up recovery from explosions when equipped. Below you can find all the Halo Infinite Foundation collectible locations in the order they appear in the mission. Look in the direction of the skull and you will see another platform where you can grapple to. The location is quite dark and it might be a little difficult to spot the platform.