Here is the full list of all 31 Iron Fisticle achievements.
Collect all hint books
Get garlic breath
Get the golden bananas
Complete the bonus game
Complete the game
Collect a giant piece of cake
Collect 100 treasures
Collect all rainbow gems
Reach max level
Get the golden turd
Complete the third floor
Collect 5 diamonds
Collect 1000 coins
Make lemonade
Collect 100 items in the ledger
Complete the second floor
Collect 10 golden goblets
Collect all letters spelling B-O-N-U-S
Level up ten times
Kill a golem
Kill 10 enemies using dash
Open 100 chests (any type)
Complete the first floor
Kill 1000 Frankies
Complete a room when entering with only 1 health
Complete The Catacombs
Buy a gold item in the shop
Complete The Graveyard
Level up once
Complete the first room
Complete a room without losing any health