Here we have an alternative basement to the Watchtower that I used for my final battle. In this, the 12 points on the ring had orbs that could be twisted to teleport layers to a 1d13 points (the twelve other orbs or the center) or held to cause a beam of light to strike the boss at the center of the room. If players had two opposite beams of lighting shining on the boss, her shield preventing damage went down and other players could hit her. Complicating this were 12 shades of the boss on the 12 clock-points jutting out towards the island, dealing minor damage and dying in one successful hit, but regenerating every time the boss lost her shield. After three hits, the orbs allowing the beams to lower the shields overheated and players would have to realign.
I added stairs in roll 20 to the room, along with chests and furniture, but left these blank on the map so other campaigns could use it aside from the watchtower. Any campaign with underground environments might find a use for this map!