Eberron is the main physical world. It has three Coils. Planes that exist alongside Eberron include:
■Dolurrh – The Shadowfell
■Thelanis – The Feywild
■Dal Quor – Region of Dreams demiplane.
The Mortal World of Eberron is made up of six continents surrounded by oceans and a vast underworld.
■Khyber – Underdark. Eberron underworld existing beneath the continents and oceans.
Adventure primarily takes place in the central region of Khorvaire known as the Five Nations.
■The Kingdom of Aundair (Scholarly)
■The Kingdom of Breland (Cosmopolitan)
■The Kingdom of Karrnath (Militaristic)
■The Kingdom of Thrane (Theocratic)
■The Mournlands of Cyre (Formerly Cyre, but now an uninhabited haunted zone.)
Southeast is the small continent of Aerenal, ruled by elves. Due south is the jungle continent of Xen’drik, once ruled by an empire of giants that collapsed, now largely wilderness, with some areas under tribal dominion of the drow (with a polar continent to the south called Everice). Frostfell is an unexplored land of ice in the north. The other two main continents are Sarlona (a continent ruled by quori, creatures from the Region of Dreams) and Argonnessen (a continent inhabited by dragons). The world of Eberron has twelve moons; some sages believe there is a thirteenth moon that has vanished or is invisible to the naked eye.
“Eberron” is also referred to as the Dragon Between. Siberys, the Dragon Above, is the name given to the planetary rings which surround the planet. Khyber, the Dragon Below, is the name given to the underworld, and is similar to the Underdark in many other settings. According to the creation story, the world was formed when the progenitor wyrms changed their form into what they are now. Siberys created the dragons, Eberron created humanoids and other “lower races”, and Khyber created the “demons” of the world.
The Dragonmarked Houses are thirteen extended families which control most business throughout Khorvaire. Within the houses, only a small percentage of every generation manifest dragonmarks, which are marks on the body that grant spell-like abilities to those born with them. These dragonmarks are designated by taking the Least, Lesser or Greater Dragonmark feat or taking levels in the Dragonmark Heir prestige class. There used to be thirteen dragonmarks but only twelve remain. Each family possesses only one type of mark, and only one or two races can manifest a particular type of mark.
With the exception of House Phiarlan and House Thuranni (which both possess the Mark of Shadow), each house exclusively has one type of dragonmark.
Dragonmarks come in five forms: aberrant, least, lesser, greater, and Siberys. Aberrant dragonmarks are deviations from normal marks and are not recognized by the dragonmarked houses. People who have aberrant dragonmarks are commonly believed to have been warped by Khyber, the Dragon Below.
Another family line known as House Vol possessed an additional dragonmark known as the Mark of Death, but that line was mostly destroyed in a conflict between dragons and other elves. Only one heir remains today (named Erandis d’Vol), but because she is a lich she cannot use her dragonmark. However, she tries to gather information to restore the mark through the Order of the Emerald Claw and the religion known as the Blood of Vol.
The worst punishment for a member of a dragonmarked house is called excoriation. It is similar to excommunication in that the other members of the house are not allowed to have any contact with the excoriate under threat of severe punishment themselves. Excoriates may not even avail themselves of the publicly-available services their house provides. Excoriation is the punishment for only the worst offenses that dishonor the house. In prior times, the house would actually flay the dragonmark from the person’s body. If the person survived excoriation, the missing dragonmark would regrow on a different part of the body and continue to function, but its use caused severe pain to the person.