Borderlands 4 How to Unlock the Legendary Swarm Grenade

Swarm is an explosively-fun Grenade that spawns additional homing Grenades upon detonating. Once thrown, the rest of the work is done for you!

It's a great tool for dealing with clumps of smaller enemies, allowing you to focus your attention towards any more threatening foes.

Unlock Location:

• Unlock the Hungering Plane sub-region of the Fadefields.
• Access the Prospects Drill Site activity, where Sidney Pointylegs spawns.

Farm Method:

• Defeat Sidney Pointylegs at the drill site.
• Use the Encore Machine to repeat the battle.
• Optionally, after completing the story, spend Eridium to face the Moxxi's Big Encore version of Sidney for increased drop chances.
• Farm until Swarm drops.