Cocytus

The Cocytus (コキュートス, Kokyūtosu), also known as the "Demon World" (魔王界, Maō-kai), the "Heart of the Dark Area" (ダークエリアの中心部, Dākueria no chūshin-bu), the "Den of Demons" (悪魔の巣窟, Akuma no sōkutsu) and "Pandemonium" (パンデモニウム, Pandemoniumu), is an area connected to all Dark Areas from all Digital Worlds. There is only one Cocytus, with the location shared by every Dark Area, with Cocytus acting as the deepest layer within each Dark Area, connecting them all to each other. Grand Dracumon, Gulfmon, and the Seven Great Demon Lords have their castles and base of operations here..

The Cocytus was born from the darkness of human hearts, wich have contaminated the Digital World. The Cocytus is where drifting evil will within the Net collects. It is here that the body of Lucemon: Satan Mode resides sealed, and it appears to be connected directly to Gulfmon's "Maw"..

=Appearances=

Barbamon sends the protagonists to the Pandemonium.

The Seven Great Demon Lords take residence in the Cocytus. Lucemon (X-Antibody) had Keramon (X-Antibody) wait in the Cocytus and after the Demon Lords were defeated it teleported their bodies to the Cocytus and then had Keramon warp evolve to Diablomon (X-Antibody) and fuse with the bodies of the defeated Demon Lords to create Ogudomon (X-Antibody).

Lucemon: Falldown Mode and Beelzebumon lived in the Demon World inside the Dark Area alongside the rest of the Seven Great Demon Lords.

Reference
=See also=
 * Dark Area
 * Dark Area (Iliad)‎‎
 * Dark Area (Witchelny)‎