Games like Power Up!
Games like Power Up! include Slay the Spire, Inscryption, Balatro, Slay the Spire 2, and Griftlands. We matched them by the tags players give Power Up! on Steam (Card Battler, Deckbuilding, Story Rich, Roguelike Deckbuilder, and Card Game): closest matches first, and among equally close ones the better-known games.

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

Inscryption
Shared: Card Battler · Story Rich · Deckbuilding

Balatro
Shared: Deckbuilding · Card Game · Roguelike Deckbuilder

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

Griftlands
Shared: Card Battler · Deckbuilding · Roguelite

Dicey Dungeons
Shared: Card Battler · Deckbuilding · Roguelike Deckbuilder

Monster Train
Shared: Card Battler · Deckbuilding · Card Game

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

Wildfrost
Shared: Card Battler · Roguelike Deckbuilder · Card Game

DICEOMANCER
Shared: Card Battler · Card Game · Roguelike Deckbuilder

Commander Quest
Shared: Roguelike Deckbuilder · Card Game · Deckbuilding

9 Kings
Shared: Deckbuilding · Card Game · Strategy

Library Of Ruina
Shared: Story Rich · Deckbuilding · Card Game

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

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

Overdungeon
Shared: Roguelike Deckbuilder · Card Battler · Deckbuilding

Chrono Ark
Shared: Roguelike Deckbuilder · Roguelite · Card Game

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

Ratropolis
Shared: Deckbuilding · Card Battler · Roguelite

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

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

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

Tainted Grail: Conquest
Shared: Deckbuilding · Card Game · Story Rich

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