Epheotus is one of the three continents of the world that Arthur Leywin (formerly Grey) reincarnated into, homeland of the Asuras. It's said by Windsom that the continent isn't nearly as large as Dicathen or Alacrya. 
Much of the economy of both Dicathen and Alacrya were developed mimicking the systems used in Epheotus. The similarities between the land of Asuras and the two surface continentes are many, specifically on how society works. 
Epheotus was once divided into three factions, each of them being composed of multiple clans. The leader clan of each one of them had specific priorities, and the clans followed them the faction whose ideals align more with their own.
Many different landscapes are seen within Epheotus, including a forest and a desert. It is shown to have a wide variety of flora and fauna that are different to those seen in Dicathen and presumably Alacrya too. Animals Arthur has encountered so far include titan bears, silver panthers and raptor squirrels which are said to be unlike what he has encountered before.[Citation needed]
No information is found where Epheotus is in contrast to the other continents as the Asura all use portals to move between Dicathen and Epheotus and presumably Alacrya and Epheotus too. The only thing we can assume is that it is relatively far (or well hidden) to Dicathen as it's residents don't know of it's existence and have thus never stumbled upon it's location. It is unknown what the Alacryans know of Epheotus except that it is where the Vritra hailed from.