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