Fuse is a 
Daedalus Grenade
Artillery Fuse Fortified position makes the Grenade have a fuse time of 4-5 seconds before Detonating.
Use your favourite features in-game with our Desktop AppBorderlands 4 How to Unlock the Legendary Fuse Grenade
Legendary Loot
Ordnance
Overview
How to Unlock
Unlock Location:
- Progress through the story until reaching "Unpaid Tab" a Main Quest in Queen's Cradle area.
- You will encounter Driller Hole, Minor campaign boss.
Farm Method:
- Defeat Driller Hole and finish the main story mission.
- After completing the story mission, return to his arena.
- Use the Encore Machine nearby to reset the fight.
- Repeatedly defeat Driller until Artillery Fuse drops.
Loveless
Plague Star