Unholy Heights combines elements of Tower Defense and Apartment Management Simulation, offering players a distinctive gameplay experience on PlayStation 4. In this game, players assume the role of the Devil, managing a tenement building solely for monsters. The objective is to attract various monsters as tenants, charge them rent, and maintain their happiness through furniture and amenities. This management aspect is crucial as it influences the monsters' willingness to fight against invading heroes.

As players navigate this quirky world, they must also defend their building from relentless heroes seeking to thwart their plans. The gameplay features an intuitive mouse-based control scheme to command monsters in battle, and players can interact with over 20 different monster species, each with unique traits and behaviors. The game also offers quests to unlock new monsters and furniture, ensuring a fresh experience with every playthrough.