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