Eitr is a mythical substance in Norse mythology, appearing as an obstacle in Tomb Raider: Underworld. This liquid substance is the origin of all living things, the first giant Ymir was conceived from eitr. The substance is supposed to be very poisonous and is also produced by Jörmungandr (the Midgard serpent) and other serpents.
The word eitr exists in most North Germanic languages (all derived from the Old Norse language) in Icelandic eitur, in Danish edder, in Swedish etter. Cognates also exist in Dutch ether, in German Eiter (lit. pus),in Old Saxon ĕttar, in Old English ăttor. The meaning of the word is very broad: poisonous, evil, bad, angry, sinister etc.
Tomb Raider Underworld
Eitr plays a big role in Underworld and Lara comes across an abundance of this mythological substance in the game. The eitr is responsible for the creation of Thralls, which are dead creatures that have been exposed to eitr for a prolonged period. During the course of the game, the eitr is shown to produce undead thralls as guardians, assumed to be victims who had fallen or been thrown into the eitr in the past. Lara will first come across the eitr in Xibalba while she is looking for the pieces necessary to complete Thor's Hammer. Lara should refrain from making any contact with the eitr, or else she will die instantly from the poisonous substance. She also comes across a wide variety of Thralls in the game that have been created by the eitr.
Once inside Helheim, she will come across waterfalls and pools of the eitr. She will also come across her mother Amelia Croft, and much to her horror, discovers that she has turned into a Thrall due to exposure to the eitr. Lara will eventually come across the Midgard Serpent and Jacqueline Natla, which is surrounded by a sea of eitr. After dismantling the Midgard Serpent, Lara is able to pin Natla into the eitr with Thor's Hammer.
The villain of the game, Natla, is defeated when she is thrown into the poisonous eitr at the game's conclusion. Natla, unlike the others who had fallen in, survives with her mind intact, but is later drowned in eitr in the conclusion of Lara's Shadow.
Lara's Journal Entry
In Norse myth, eitr was an elixir that bestowed eternal life to the gods, but paradoxically it was a poison that came from serpents, like the Midgard Serpent. This is similar to the Hindu concept of amrita, or ambrosia to the Greeks. Only the Norse came the closest to the literal truth: that the substance was indeed a poison, and in fact only gave the appearance of eternal life in the animation of corpses.
- Svenska Akademiens Ordbok, entry for Etter