Games like Slay the Spire
Games like Slay the Spire include Balatro, Slay the Spire 2, Dicey Dungeons, Wildfrost, and 9 Kings. We matched them by the tags players give Slay the Spire on Steam (Roguelike Deckbuilder, Card Game, Card Battler, Roguelike, and Deckbuilding): closest matches first, and among equally close ones the better-known games.

Balatro
Shared: Card Game · Roguelike Deckbuilder · Roguelike

Slay the Spire 2
Shared: Card Game · Roguelike · Roguelike Deckbuilder

Dicey Dungeons
Shared: Roguelike Deckbuilder · Card Battler · Deckbuilding

Wildfrost
Shared: Roguelike Deckbuilder · Card Battler · Card Game

9 Kings
Shared: Card Game · Roguelike · Roguelike Deckbuilder

Dungeons & Degenerate Gamblers
Shared: Roguelike Deckbuilder · Card Game · Roguelike

Die in the Dungeon
Shared: Roguelike · Card Game · Roguelike Deckbuilder

Yao-Guai Hunter
Shared: Roguelike Deckbuilder · Card Game · Roguelike

Vampire Crawlers: The Turbo Wildcard from Vampire Survivors
Shared: Card Battler · Roguelike · Deckbuilding

Monster Train
Shared: Card Battler · Card Game · Deckbuilding

Roguebook
Shared: Card Game · Deckbuilding · Strategy

Super Fantasy Kingdom
Shared: Roguelike · Strategy · Card Game

Inscryption
Shared: Card Game · Card Battler · Deckbuilding

Astrea: Six-Sided Oracles
Shared: Roguelike Deckbuilder · Card Battler · Card Game

Black Jacket
Shared: Roguelike Deckbuilder · Card Game · Roguelike

Griftlands
Shared: Card Battler · Deckbuilding · Card Game

Blood Card
Shared: Roguelike Deckbuilder · Card Battler · Card Game

Banners of Ruin
Shared: Roguelike Deckbuilder · Card Battler · Card Game

Breachway
Shared: Card Game · Roguelike · Roguelike Deckbuilder

Ratropolis
Shared: Card Battler · Deckbuilding · Card Game

Guild of Dungeoneering Ultimate Edition
Shared: Roguelike Deckbuilder · Roguelike · Card Game

DICEOMANCER
Shared: Card Game · Roguelike Deckbuilder · Card Battler

Deathless. The Hero Quest
Shared: Roguelike Deckbuilder · Card Game · Deckbuilding

My Card Is Better Than Your Card!
Shared: Card Game · Roguelike · Roguelike Deckbuilder