For this achievement you need to complete every mission in the General Knoxx DLC, there are 43 missions that you need to complete and hand in.
The missions come from many areas from many people:
• T-Bone Junction (Bounty Board, Athena later into the game, Scooter and Marcus)
• The Crimson Tollway (Agent 01)
• Parched Fathoms (Moxxi)
• Sunken Sea (Thirsty the Midget)
• Road's End (Radar Device)
• Lockdown Palace (Claptrap)
• Circle of Duty (Circle Director)
The 43 missions are:
• Wanted: Dead!
- Hera - Outside Moxxi's place.
- Minerva - First outpost place you reach in The Ridgeway.
- Ceresia - When you enter Road's End
- Helicon - A little bit before entering the Armory
(To turn this mission in, go upstairs to where you opened the roadblock at the beginning which is where the compass marker is pointing and click the wanted posters on the east wall.)
• Armory Assault
• Bridging the Gap
• Athena Set Up Us The Bomb
• Knoxxed Out
• This Bitch is Payback
• This Bitch is Payback, pt. 2
• Loot Larceny
• Code Breaker: Analysis
Atlas Informant Main Storyline
• Scooter? But I Don't Even Know Her
• New Recruit – Obtain from T-Bone Bounty Board
• Medal of Duty
Claptrap in Lockdown Palace
• Claptrap Rescue
Lance ECHO Main Storyline
• Code Breaker: Time is Bullets
Marcus – Make sure you don’t have Super-Marcus Sweep and It’s Like Chrismas! Active at the same time
• Core Collection
• Mop Up
• Super-Marcus Sweep
• Local Trouble
• It's Like Christmas!
• Prison Break: Road Warrior
• Prison Break: Over the Wall
• Prison Break: Try Not to Get Shanked
• Thrown for a Loop
• Stain Removal
Radar Device - Road's End
• Lost Lewts
• Boost the Monster
• You've Got Moxxi: Roadblock
• You've Got Moxxi: Moxxi's Red Light
• OMG APC
T-Bone Bounty Board
• Big Crimson Brother is Watching
• Drifter Lifter
• Power Leech
• Road Rage
• You. Will. Die.
Thirsty the Midget - Sunken Sea
• Purple Juice!
• Little People, Big Experiments