There are two dungeons in the game currently, the maze dungeon and the arena dungeon.
The maze dungeon is a randomly generated dungeon consisting of combat rooms connected by hallways. Combat rooms lock upon entry, and require the player to fight and defeat a series of monsters before advancing. Combat rooms often have traps in the room, and sometimes have specific modifiers during the fight (such as increased environmental damage). In the hallways between combat rooms, random monsters and various forms of loot can spawn, as well as traps.
The types of loot you can find while exploring the hallways includes treasure chests, which grant an unlocked weapon when approached, curse altars, which grant you a blessing in exchange for a curse, upgrade altars, which allow you to choose from three different upgrades to give yourself, and weapon upgrade pools, which allow you to add a benefit to a weapon. You can also find Health and Mana Points recovery altars.
The arena dungeon consists of a large square arena room in which you fight waves of enemies with traps and weapons dropped by enemies. The enemies spawn in a wave like form throughout the game.
The sandbox is an open area with two gates on each side, and a safe part with a staircase leading up to it. In the sandbox you can spawn enemies, weapons, adjust strength and health and much more. To the left of the weapon spawning area you choose your allies and to the left you choose your enemies.