Games like Happy Treasure King
Games like Happy Treasure King include Thronefall, Orcs Must Die! 3, Orcs Must Die! 2, Orcs Must Die!, and PUBG: BATTLEGROUNDS. We matched them by the tags players give Happy Treasure King on Steam (Action, Strategy, Tower Defense, Third-Person Shooter, and Relaxing): closest matches first, and among equally close ones the better-known games.

Thronefall
Shared: Strategy · Tower Defense · Action

Orcs Must Die! 3
Shared: Tower Defense · Strategy · Action

Orcs Must Die! 2
Shared: Action · Tower Defense · Strategy

Orcs Must Die!
Shared: Action · Tower Defense · Strategy

PUBG: BATTLEGROUNDS
Shared: Action · Shooter · Third-Person Shooter

s&box
Shared: Action · Building · Shooter

Bloons TD 6
Shared: Strategy · Tower Defense · 3D

Kingdom Rush - Tower Defense
Shared: Strategy · Tower Defense · Action

Kingdom Rush Origins - Tower Defense
Shared: Strategy · Tower Defense · Building

Warhammer 40,000: Space Marine 2
Shared: Action · Third-Person Shooter · Action-Adventure

Planet Coaster
Shared: Strategy · Building · Relaxing

World of Warships
Shared: Third-Person Shooter · Shooter · Strategy

ISLANDERS
Shared: Strategy · Relaxing · Building

Bee Island
Shared: Strategy · Tower Defense · Action

Marvel Rivals
Shared: Third-Person Shooter · Action · Strategy

Ratchet & Clank: Rift Apart
Shared: Action · Action-Adventure · Third-Person Shooter

Sanctum 2
Shared: Tower Defense · Strategy · Action

House Flipper
Shared: Relaxing · Building · Action

Tomb Raider Game of the Year
Shared: Action · Third-Person Shooter · Action-Adventure

Kingdom Rush 5: Alliance TD
Shared: Strategy · Tower Defense · Building

Bloons TD 5
Shared: Strategy · Tower Defense · Action

Squirrel with a Gun
Shared: Action · Third-Person Shooter · Action-Adventure

007 First Light
Shared: Third-Person Shooter · Action-Adventure · Shooter

Kingdom Rush Vengeance - Tower Defense
Shared: Strategy · Tower Defense · Action