Here is the full list of all 31 Elephantasy: Flipside achievements.
Find a Golden Needle.
Find a Radio.
Find Death's Key.
Find a Wish.
Find someone's Sword.
Obtain your first Gem.
Collect all 50 Gems.
Obtain your first chunk of Ore.
Collect all 30 chunks of Ore.
Obtain your first Key.
Collect all 50 Keys.
Improve an Item.
Improve all eight Items.
Rescue Mimi.
Defeat Duke.
Rescue Rocky.
Find Font.
Bribe Carlisle.
Bribe Vigo.
Bribe Delphis.
Rescue Death.
Get Ending #0.
Get Ending #1.
Get Ending #2.
Escape after getting Ending #2.
Get Ending #3.
Bring Polnareff to the Moon.
Get 100% completion.
Just barely beat Goldman's best time in a race.
Help cultivate all four kinds of Herbs.
Find Puppy, the shopkeeper, off the clock.