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