Full list of all 80 Borderlands Game of the Year Enhanced achievements. It takes around 60-80 hours to unlock all of the achievements on Windows.
Emerged victorious from an arena match
Killed Crawmerax the Invincible
Killed each of the loot midgets
Completed a crazy request for Tannis
Paid for a worthless tour of the world's largest bullet
Killed the Interplanetary Ninja Assassin Claptrap
Killed Commandant Steele-trap
Killed Dr. Ned-trap
Killed General Knoxx-trap
Destroyed a Lancer while in a Racer
Killed an enemy with the Siren's action skill
Killed 15 enemies with the Berserker's action skill
Killed 15 enemies with the Soldier's action skill
Completed all missions in the Rust Commons
Killed the Vault Boss
Discovered Eridian Promontory
Discovered Crimson Lance Enclave
Won a duel without taking damage
Killed Flynt
Killed the Rakk Hive
Raced around the Ludicrous Speedway in record time
Discovered Trash Coast
Killed Krom
Discovered Krom's Canyon
Killed 25 enemies with shock weapons
Found 25 oil cans
Collected 15 Claptrap bobbleheads
Completed all missions in the Arid Badlands
Killed an enemy plumber-style
I bet you never thought you'd be here
Discovered The Scrapyard
Completed 5 missions in the Rust Commons
Won a duel against another player
Play with at least two other players.
Completed 15 missions in co-op
Equipped a class mod for your character
Killed Sledge
Defeated the Rakk Hive, the Vault Boss, Sledge, Krom, or Flynt in a co-op game
Sold 50 guns to a shop
Discovered Headstone Mine
Discovered Sledge's Safe House
Killed 5 Rakk in under 10 seconds
Killed 25 enemies by ramming them with any vehicle
Completed the "Braaaaaaaaaaaaains!" mission
Rescued a groupmate from death in a co-op game
Completed all missions in Secret Armory
Completed 5 missions in the Arid Badlands
Discovered Skag Gully
Killed 25 enemies with incendiary weapons
Killed 25 enemies with corrosive weapons
Killed 25 enemies with explosive weapons
Killed 15 enemies with the Hunter's action skill
Earned $1,000,000
Mastered the technology of Pandora
Completed the "House of the Ned" mission
Completed the "Jakobs Fodder" mission
Killed Ned...sort of
Killed Ned. Again.
Applied an elemental artifact
Earned level 5
Earned level 10
Earned level 20
Earned level 30
Earned level 40
Earned level 50
Reached proficiency level 10 with any weapon type
Rescued enough Claptraps to earn 42 inventory slots
Completed the lesser challenge in all 3 coliseums
Completed the larger challenge in the Hell-Burbia coliseum
Completed the larger challenge in The Angelic Ruins coliseum
Completed the larger challenge in The Gully coliseum
Completed each of the larger challenges in all 3 coliseums
Built the New Car: Monster
Rescued Athena
Destroyed Lance Depot
Reached Level 61
Found all 6 Claptrap statues
Collected 5 3D glasses
Collected 3 panties, 5 fish in a bag, and 15 pizzas
Reached Level 51