Here is the full list of all 27 Solitairica achievements.
Unlock a second deck
Visit the Cliffs of Mythos
Battle all 18 enemy types
Visit Tangleslime Swamp
Cause the enemy to sacrifice the last card
Visit the Ruinous Bog
Match every numeral in a single streak
Visit the Blandlands
Upgrade your first card in any deck
Collect a wildstone from a card
Start a new journey after your heart breaks the first time
Have your heart broken
Match 10 cards in a row
Visit the Meadows of Madness
Unlock the Warrior deck
Enter Castle Stuck
Defeat Emperor Stuck
Collect 50+ coins from a single card
Break your heart by taking fatal damage on the last card
Defeat the enemy without using any spells
Fill the bar for all energy types.
Use Cosmic Inversion to go from 1 health to full
Buy all 3 potions in a single journey
Encounter all enemy traits
Buy every item in the game
Buy every spell in the game
Defeat Emperor Stuck with every deck