Here is the full list of all 46 Adventure Time: Explore the Dungeon Because IDK achievements worth 1,000 gamerscore.
Complete all of Starchy's Quests.
Collect every Token
Collect every Sub-Weapon
Uncover Bubblegum's dark secret.
Complete all of Susan Strong's Quests.
Overcome the Guardians' punishment.
Fully upgrade Finn.
Complete all of Mr. Pig's Quests.
Free Flame Princess.
Locate every Familiar
Entered the Nightosphere
Free the Earl of Lemongrab.
Complete all of Tree Trunks' Quests.
Grab 50 Treasures on a single Treasure Floor.
Weather Goliad and Stormo's psychic assault.
Pick up every Item pickup at least once.
Rescue the Hyoomans.
Upgrade a Sub-Weapon into a stronger one.
Survive a Monster Floor.
Assist Gunter with a feisty feline.
Eat every Food item at least once.
Perform a perfect block
Upgrade a character's Imagination.
Put Ice King in his place.
Upgrade a character's Focus.
Buy something from the shop.
Outrun the stampeding prisoners.
Receive a Curse.
Return from the Dungeon alive.
Upgrade a character's Rowdiness.
Outsmart the Demon Cat.
Used a Special Attack.
Upgrade a character's Thumps.
Complete a Quest for the Princess.
Max out Jake's stats
Max out Marceline's stats
Max out Cinnamon Bun's stats
Max out Lumpy Space Princess's stats
Max out Ice King's stats
Max out Lemongrab's stats
Max out Flame Princess's stats
Complete Bubblegum's Quests
Travel 15 Floors in one Nightosphere run
Travel 25 Floors in one Nightosphere run
Travel 50 Floors in one Nightosphere run
Find all of BMO's game cartridges