Games like Party Demon
Games like Party Demon include Slay the Spire 2, Balatro, Slay the Spire, Inscryption, and Emberward. We matched them by the tags players give Party Demon on Steam (Strategy, Deckbuilding, Card Game, Roguelike, and Tower Defense): closest matches first, and among equally close ones the better-known games.

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

Balatro
Shared: Card Game · Deckbuilding · Roguelike

Slay the Spire
Shared: Card Game · Deckbuilding · Roguelike

Inscryption
Shared: Card Game · Deckbuilding · Roguelike

Emberward
Shared: Strategy · Tower Defense · Deckbuilding

9 Kings
Shared: Strategy · Roguelike · Card Game

Loop Hero
Shared: Deckbuilding · Roguelike · Card Game

Ratropolis
Shared: Deckbuilding · Strategy · Card Game

The King is Watching
Shared: Roguelike · Tower Defense · Base Building

Heretic's Fork
Shared: Deckbuilding · Strategy · Tower Defense

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

Monster Train
Shared: Card Game · Deckbuilding · Roguelike

Super Fantasy Kingdom
Shared: Strategy · Roguelike · Card Game

Die in the Dungeon
Shared: Strategy · Deckbuilding · Roguelike

Griftlands
Shared: Deckbuilding · Card Game · Roguelite

RACCOIN: Coin Pusher Roguelike
Shared: Strategy · Deckbuilding · Roguelike

Dicey Dungeons
Shared: Deckbuilding · Roguelike · Strategy

Kingdom Rush - Tower Defense
Shared: Strategy · Tower Defense · 2D

Peglin
Shared: Deckbuilding · Roguelike · Strategy

Rogue Tower
Shared: Strategy · Tower Defense · Roguelike

DICEOMANCER
Shared: Strategy · Card Game · Deckbuilding

Kingdom Rush 6: Genesis TD
Shared: Strategy · Tower Defense · Base Building

Monster Train 2
Shared: Card Game · Deckbuilding · Roguelike

Nubby's Number Factory
Shared: Strategy · Roguelike · Deckbuilding