Games like SPELLHACK!!
Games like SPELLHACK!! include Slay the Spire, Balatro, Slay the Spire 2, Dicey Dungeons, and Inscryption. We matched them by the tags players give SPELLHACK!! on Steam (Roguelike Deckbuilder, Real Time Tactics, Survival, Action, and Card Battler): closest matches first, and among equally close ones the better-known games.

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

Balatro
Shared: Roguelike Deckbuilder · Card Game · Deckbuilding

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

Dicey Dungeons
Shared: Roguelike Deckbuilder · Card Battler · Roguelite

Inscryption
Shared: Card Battler · Card Game · Deckbuilding

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

Stacklands
Shared: Survival · Card Game · Card Battler

Ratropolis
Shared: Card Battler · Deckbuilding · Roguelite

Wildfrost
Shared: Roguelike Deckbuilder · Card Battler · Card Game

Monster Train
Shared: Card Battler · Roguelite · Deckbuilding

Overdungeon
Shared: Roguelike Deckbuilder · Card Battler · Strategy

9 Kings
Shared: Roguelike Deckbuilder · Strategy · Deckbuilding

Dungeons & Degenerate Gamblers
Shared: Roguelike Deckbuilder · Card Battler · Deckbuilding

Hand of Fate 2
Shared: Roguelike Deckbuilder · Action · Deckbuilding

One Step From Eden
Shared: Roguelite · Card Battler · Action

DICEOMANCER
Shared: Roguelike Deckbuilder · Card Battler · Card Game

Heretic's Fork
Shared: Roguelike Deckbuilder · Deckbuilding · Action

ROUNDS
Shared: Action · Roguelite · Deckbuilding

Die in the Dungeon
Shared: Roguelike Deckbuilder · Deckbuilding · Card Battler

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

Commander Quest
Shared: Roguelike Deckbuilder · Card Game · Deckbuilding

Hand of Fate
Shared: Roguelike Deckbuilder · Deckbuilding · Action

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

Griftlands
Shared: Card Battler · Roguelite · Deckbuilding