Insert butt-core in bomb is an objective in the Story Mission, Shooting The Moon in Borderlands 2: Commander Lilith and the Fight For Sanctuary
- Back in Munitions Loading, go to the middle of the room.
- Once again interact with the missile you have been building with Tiny Tina.
- In the rear of the missile, you will need to insert the new Power Core.
- With it slotted in, the missile is about ready to go.