Delver is set in an old dungeon simply named "The Dungeon". The Dungeon used to consist of 6 randomly generated floors, followed by a static end-game floor but this have changed as of release.
The game starts outside at the Camp level where player can buy some scrolls or gear, pet a dog or listen to bard. The entrance to the Dungeon is located nearby.
The first 2 floors are Dungeon floors. These consist of various buildings along with few open areas and few caves. Various bandits inhabit the place. They are followed by a small Well level where player can buy more gear or expand their bag or belt.
The next 2 floors are Caves. They consist of big caves with deep pits and, sometimes, lava pools. Several insects can be found there. It is followed by small Lost City level.
The next 2 floors are Sewers. Various waterways consists of big rooms and small passages with passage on the edges and water in the middle. Goblins live here. It is followed Breach level where player can buy scrolls for last time.
Floors 7-8 consist of Ruins. Ancient skeletons inhabit these lava filled structures. Countless traps are present as well.
After exiting level 8 the player arrives in Yithidia, the final level in the game. It consists of little passage to a purple portal that leads to an arena where player have to battle the Lich to obtain Yithidian Orb.
When the Orb is obtained the played have go return back to the surface. The Dungeon however will start to shake violently with purple explosions occuring that damage player slightly and create fires. The Dungeon however will not collapse if the player takes too long, but enemy spawn rate is increased. On the way back Lich will avait at every ladder leading back.
Each floor deeper is harder than the last, having better loot and stronger monsters, with certain enemies only on different floors. The character cannot exit the dungeon without the Yithidan Orb, so he must progress all the way down, defeat all the creatures, and recover the orb in order to escape successfully.
Dungeon, Caves, Sewers and Ruins are randomly generated levels while Camp, Well, Lost City, Breach and Yithidia are static ones.