Killed an enemy plumber-style

Killed 25 enemies with explosive weapons

Defeated the Rakk Hive, the Vault Boss, Sledge, Krom, or Flynt in a co-op game

Discovered Headstone Mine

Killed 25 enemies by ramming them with any vehicle

Rescued a groupmate from death in a co-op game

Won a duel without taking damage

Sold 50 guns to a shop

Killed 15 enemies with the Hunter's action skill

Killed an enemy with the Siren's action skill

Killed 15 enemies with the Berserker's action skill

Earned level 5

Completed 5 missions in the Arid Badlands