Build grand chambers and round rooms with these big 4" pieces. The insert wall can be used to create a solid curve, can be removed to make a doorway, can be lifted out during play as a secret door. The insert also has a hidden metal plate so it can hold magnetic accessories. The backfill piece gives the curve a clean 4x4 footprint for building in-line, or can be used to create gently curving negative space builds. Sculpted in the Vaulted Dungeon style with columns and arches on the walls, and painted in the NEW Sinister scheme.