The Deep Abyss is a metaroom coded by Grendel Man with art by Mea. The Deep Abyss is based on the dark ocean floors, with thermal vents heating the waters.
The initial version was released for the CCSF 2013. A later version with plant life was released for New Year's 2014. It overlaps with the Xmas Room.
It is available for download at The Realm.