Games like House Rules 21
Games like House Rules 21 include Balatro, Poker Night at the Inventory, Plants vs. Zombies GOTY Edition, Game Dev Tycoon, and Texas Hold'em Poker: Pokerist. We matched them by the tags players give House Rules 21 on Steam (Strategy, Casual, Card Game, Poker, and 2D): closest matches first, and among equally close ones the better-known games.

Balatro
Shared: Card Game · Strategy · Singleplayer

Poker Night at the Inventory
Shared: Casual · Card Game · Gambling

Plants vs. Zombies GOTY Edition
Shared: Strategy · Casual · 2D

Game Dev Tycoon
Shared: Strategy · Casual · Indie

Texas Hold'em Poker: Pokerist
Shared: Casual · Card Game · Poker

Plague Inc: Evolved
Shared: Strategy · Casual · Indie

Slay the Spire
Shared: Card Game · Strategy · Singleplayer

Bloons TD 6
Shared: Strategy · Casual · Singleplayer

Slay the Spire 2
Shared: Card Game · Strategy · Indie

Slots & Daggers
Shared: Strategy · Casual · Gambling

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

Zup! S
Shared: Casual · 2D · Indie

911 Operator
Shared: Strategy · Casual · Indie

Ballionaire
Shared: Casual · 2D · Strategy

RACCOIN: Coin Pusher Roguelike
Shared: Strategy · Casual · Singleplayer

Mini Metro
Shared: Strategy · Casual · Indie

Library Of Ruina
Shared: Card Game · Strategy · Singleplayer

UNO
Shared: Card Game · Casual · Strategy

Rana Card
Shared: Casual · Card Game · Strategy

The Four Kings Casino and Slots
Shared: Card Game · Casual · Gambling

100% Orange Juice
Shared: Strategy · Card Game · Casual

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

Circle Empires
Shared: Strategy · Casual · Indie

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