Deadlands

The Deadlands is the name given to the realm of the Daedric Prince Mehrunes Dagon. Formed to be an expression of Dagon's destructive sphere, the Deadlands are an inhospitable nightmare of lava and molten rock, pocked with islands where Dagon's servants, the Dremora, carry out his works in immense, spike towers. The sky perpetually storms, the natural astrology of Oblivion perpetually burning red, casting dark shadows over the entire realm. Among the Daedric creatures that roam the wastes are Scamps, Clannfear, Daedroths, Flame Atronachs, Frost Atronachs, Storm Atronachs, Spider Daedra, and Xivilai. Native flora include Harrada Roots, Bloodgrass, and Spiddal Plants. An Oblivion Gate that opens from the Deadlands appears as a spiked, molten, red and black portal in the shape of the "O" character of the Daedric alphabet.

In the final year of the Third Era, Mehrunes Dagon launched his invasion of Tamriel from the Deadlands, sending armies of Daedra against the mortal world. Sigil Towers were used to open Oblivion Gates, with Daedric Sigil Stones acting as anchors. The attack on the city of Kvatch was conducted from the area of the Deadlands known as Ganonah., and much of the Crisis was fought in the Deadlands. Ultimately, the Gates were sealed in the Battle of the Imperial City and Mehrunes Dagon's invasion failed.

Appearances
The Elder Scrolls II: Daggerfall (Indirect mention only)

The Elder Scrolls III: Morrowind (Indirect mention only)

The Elder Scrolls IV: Oblivion