Underkeep

Underkeep is a tower defence game in which the player takes the role of a dungeon’s final boss rather than the attacking hero. Adventurers march into the labyrinth and the player must stop them by digging corridors, placing monsters and laying traps along the route to the boss room. Anything placed remains after a wave ends, so the labyrinth is built up wave by wave.

The game provides 15 monsters, 12 traps and 8 special zones to work with. Walls can be used to fold the adventurers’ path back on itself so that a single trap is triggered several times. Before each wave begins, the game shows which classes are approaching. Different classes behave differently: miners break through walls, sappers defuse traps and rogues can sometimes pass straight through them. Each adventurer also has a weaker side, either physical or mental, so a warrior may resist blades but be vulnerable to magic while a mage is the reverse. Deciding how to spend gold against these weaknesses determines how far a run progresses. When a class appears for the first time, the game pauses and displays a card explaining it, including its weakness.

Defeat wipes the labyrinth but the player’s record is kept, with each new run intended to reach further than the last. Controls use the mouse for placing and removing items, with drag support for placing or removing runs of them, plus keyboard shortcuts for starting waves, opening the shop, expanding land, moving the boss room, rotating, changing game speed and accessing settings. The game supports Korean, English and Spanish.