Here is the full list of all 31 Balatro achievements.
Discover every Spectral card
Win a run on at least Black Stake difficulty
Discover a Legendary Joker
Discard at least 2500 Cards
Win a run on at least Red Stake difficulty
Play at least 2500 Cards
Win a run without rerolling the shop
Complete any challenge run
Play a Royal Flush
Get any poker hand to level 10
Discover every Tarot card
Win a run in 12 or fewer rounds
Score 1,000,000 Chips in a single hand
Reach Ante 8
Win a Run
Score 10,000 Chips in a single hand
Reach Ante 4
Win a run on at least Gold Stake difficulty
Have $400 or more during a single run
Play a Flush with 5 Wild Cards
Buy 5 Vouchers by the end of Ante 4
Break 2 Glass Cards in a single hand
Score 100,000,000 Chips in a single hand
Thin your deck down to 20 or fewer cards
Have 80 or more cards in your deck
Complete every challenge run
Discover every Planet card
Discover every Voucher
Discover 100% of your collection
Win with every deck on Gold Stake difficulty
Earn a Gold Sticker on every Joker