Full list of all 75 Borderlands 2 achievements worth 1,875 gamerscore. It takes around 60-80 hours to unlock all of the achievements in the base game.
The base game contains 69 achievements worth 1,625 Gamerscore, and there is 1 DLC pack containing 6 achievements worth 250 Gamerscore.
Gunzerked continuously for 90 seconds
Remained in Zero's Deception mode for ten seconds straight
Phaselocked 100 enemies
Completed level 1 of all non-level-specific challenges with a single character
Completed all Hammerlock's Hunt side missions
Discovered all named locations in Hammerlock's Hunt
Reached level 50
Completed the mission "The Fall of Nakayama"
Fed thy noble queen 3 times during one visit to her quarters
Won the most challenging round in Murderlin's Temple
Demonstrated your skill, or lack thereof, at rolling the magical treasure orb of many sides
Vanquished the Ancient Dragons of Destruction
Completed thy quest by rescuing yonder queen
Showed thine worst enemy, the abomination known as "The Darkness," who is the nerdiest of them all
Introduced thyself to the White Knight
Completed all side missions
Discovered all named locations
Opened the chest at the bus stop in Fyrestone
Killed Donkey Mong
Completed all Campaign of Carnage side missions
Completed the mission "Long Way To The Top"
Completed all Pirate's Booty side missions
Discovered all named locations in Oasis and the surrounding Pirate's Booty zones
Completed the mission "X Marks the Spot"
Defeated Terramorphous the Invincible
Discovered all named locations in Eridium Blight, Arid Nexus, and Sawtooth Cauldron
Defeated Jack
Completed the mission "Data Mining"
Completed the mission "Toil And Trouble"
Completed Round 5 of any Circle of Slaughter
Completed the mission "Where Angels Fear To Tread"
Discovered all named locations in The Highlands, Thousand Cuts, and Wildlife Exploitation Preserve
Completed the mission "The Man Who Would Be Jack"
Reached level 25
Unsheathed 5 swords from Immortal Skeletaurs without leaving the area
Slew Mister Boney Pants Guy
Completed the mission "The Once and Future Slab"
Completed the mission "Shoot This Guy in the Face"
Completed the mission "Wildlife Preservation"
Discovered all named locations in Sanctuary, Opportunity, and Lynchwood
Collected 10 pictures of Moxxi in Campaign of Carnage
I can't even capture it on my camera
Killed a Chubby
Had Purple-rated gear or better equipped in every slot
Wielded the Mysterious Amulet
Completed the mission "Bright Lights, Flying City"
Completed the mission "Rising Action"
Discovered all named locations in Three Horns, Tundra Express, and Frostburn Canyon
Completed the mission "A Train To Catch"
Killed a flying enemy with a thrown Tediore weapon
Allowed a Goliath to level up four times before killing him
Completed 20 side missions
Killed a Constructor without it ever building another bot
Got an item from Michael Mamaril
Completed the mission "A Dam Fine Rescue"
Completed the mission "Hunting The Firehawk"
Killed 100 enemies with the Sabre turret
Purchased 5 items from the black market
Gave Claptrap a high five
Completed the mission "Plan B"
Tipped Moxxi $10,000
Reached level 10
Completed the mission "The Road To Sanctuary"
Revived someone from "Fight for Your Life!" that is on your friends list
Completed the mission "Best Minion Ever"
Reached level 5
Completed the mission "My First Gun"
Redeemed 25 tokens
Unlocked 10 customization items
Equipped effervescent-quality gear in all slots (except class mod).
Allowed Tiny Tina to arm the moonshot cannon.
Defeated Haderax the Invincible.
Defeated the Dark Web.
Completed the mission "Paradise Found".
Activated the Backburner's firewall.