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

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

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

Balatro
Shared: Roguelike Deckbuilder · Card Game · Roguelike

9 Kings
Shared: Strategy · Roguelike · Card Game

Dicey Dungeons
Shared: Roguelike Deckbuilder · Card Battler · Deckbuilding

Inscryption
Shared: Card Battler · Card Game · Deckbuilding

Monster Train
Shared: Card Battler · Card Game · Deckbuilding

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

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

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

Wildfrost
Shared: Roguelike Deckbuilder · Card Battler · Card Game

Super Fantasy Kingdom
Shared: Roguelike · Strategy · Card Game

Griftlands
Shared: Card Battler · Deckbuilding · Roguelite

DICEOMANCER
Shared: Card Battler · Card Game · Roguelike Deckbuilder

Breachway
Shared: Card Game · Roguelike · Roguelike Deckbuilder

Touhou: Lost Branch of Legend
Shared: Roguelike Deckbuilder · Card Battler · Roguelike

Chrono Ark
Shared: Roguelike Deckbuilder · Strategy · Card Game

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

Ratropolis
Shared: Card Battler · Deckbuilding · 2D

Vault of the Void
Shared: Roguelike Deckbuilder · Deckbuilding · Card Battler

Roguebook
Shared: Card Game · Deckbuilding · Strategy

Cubic Cosmos
Shared: Roguelike Deckbuilder · Card Battler · Deckbuilding

As We Descend
Shared: Roguelike Deckbuilder · Card Battler · Card Game

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