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