Dungeon Architect: Multi-Story Dungeons theme
Dungeon Architect helps you create procedural dungeons. It lets you interactively design the look and feel of your dungeon with an intuitive graph based editor. Here is a theme designed using the Multi-story dungeon theme pack.
Dungeon Architect Forum: http://forum.unity3d.com/threads/dung...
Multi-Story Dungeon Asset: https://www.assetstore.unity3d.com/en...