New Dimension

We have the overworld, which has a bedrock floor. The nether has both a bedrock floor and bedrock roof. The End has no bedrock floor or roof. There should be a new dimension that has a bedrock roof but no floor. Im thinking it can be themed towards skulk. You spawn in the upper level near the roof. This area is full of large openings in a cave like system. Going down, the wide spaces become narrow tunnels. You get to the last level, which consist of spires that lead to a void. This new dimension can offer players a new experience, as traversing is unlike other dimensions with a roof and no floor. This dimension can offer late game players a challenge greater than other dimensions. The flora and fauna should be dangerous when provoked, but in a way that is unlike other dimensions. In terms of how to get to this dimension, and going back, the portal like structure in the ancient cities would make sense as a portal. At 0,0 in the dimension could be a portal to get back.