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