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