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