The Deadlands in the Elder Scrolls Online are a very desolate place with multiple zones and different appearances. It is Mehrunes Dagon's realm which you get to explore and therefor you will find a lot of devastation, powerful enemies and many Daedras. They are an inhospitable nightmare of lava and molten rock. The sky perpetually storms, it is a burning red, casting dark shadows over the entire realm. Natural disasters and destructive change reflect its creator's chaotic nature. The realm is covered by an ocean of lava, scattered with scorched volcanic islands and ruined structures. 

One particular part of the Deadlands will be the Sever. A tempestuous biome wracked by volatile storms where simply walking around feels like a dangerous endeavor. Lightning constantly shoots down from the sky in the shadow of the great mountain, Annihilarch's Summit.

Another biome will be the Burn, which is the traditional flame-touched hellscape. Lava and ash will be omnipresent, just as Mehrunes Dagon's presence. Especially around the massive prison known as the Blood Pit.