Full list of all 47 Exit the Gungeon achievements. It takes around 30-35 hours to unlock all of the achievements in the base game on Windows.
The base game contains 44 achievements, and there is 1 DLC pack containing 3 achievements.
Bought All Hats.
Bought All Skins.
Helped Goopton With Something Personal.
Reunited Old Red with Daisy.
Helped Flynt Avoid Embarassment.
Mastered The Deathvator.
Aced Just Dessert Golf.
Mastered The Armored Beholster.
Gave The Old Man Something To Fiddle With.
Completed Level 5 Boss Without Taking Damage.
Mastered The Chamber Of Flame.
Mastered The Mecha Bullet.
Achieved Beast Mode Level 2.
Mastered The High Priest Past.
Sated Daisuke's Craving.
Mastered The Bolt Python.
Exited The Gungeon As The Robot.
Aced Winchester's Game.
Exited The Gungeon As The Cultist.
Completed Level 4 Boss Without Taking Damage.
Mastered The Kill Shrine.
Rescued All Npcs From The Cell.
Upgraded Bello's Stools.
Unlocked All Characters.
Exited The Gungeon As The Bullet.
Mastered Gungamesh.
Exited The Gungeon As The Convict.
Mastered The Lich Dragun.
Accessed All Elevator Types.
Mastered His Majesty's Chancellor.
Exited The Gungeon As The Pilot.
Mastered The Coltaur.
Mastered The Medusalier.
Bought Something From Bello.
Bought Something From Cadence And Ox.
Exited The Gungeon As The Hunter.
Completed Level 1 Boss Without Taking Damage.
Successfully Exited The Gungeon.
Exited The Gungeon As The Marine.
Reached Max Combo.
Completed Level 3 Boss Without Taking Damage.
Completed Level 2 Boss Without Taking Damage.
Mastered The Meowitzer.
Completed Manuel's Test, A Great Achievement.
Carried Eight Weapons At Once.
Mastered The Glocktopus.
Aced Helmet Kick.