Eitr
Eitr is the primordial essence from which all things came. There are four main types of Eitr that can be woven by the humanic and beast breeds of Vikingr: Earth, Fire, Water, and Air.
Eitr has always existed through out the realms but the majority was concentrated into the essence that was each immortal’s being. When the God’s and Jotnar during Ragnarok and the remaining immortals in the War of the Shattered Gods perished they essence watered the nine realms. It is now infused with everything and every being. The concentrations are chaotic and always changing.
The Void Lands are strange pockets within the realms where no Eitr exists. Conversely Ichor lands are thought to be the places where immortals were slain because of the abnormally high concentration of Eitr.
Seidr
Seidr is the practice of weaving Eitr to manifest desires into reality. Those that practice Seidr can find Eitr in their surroundings, concentrate it, and briefly control it.
Wyrd
The Norns weave the threads of fate and those that practice Seidr can learn to look into the state of Eitr surrounding them to determine where they are on their thread. Well practiced Wyrd weavers can sometimes look down their thread into their near fate.