Nightblood

Nightbloods, also known as Natblida  (Trigedasleng) , are Grounders with the hereditary condition manifested by dark blood. Only Nightbloods can become Commanders.

History
Two years after the Nuclear Apocalypse, Becca injected herself with a substance which turned her blood black. The black fluid was used by Becca to change her genetics so that she could put A.L.I.E. 2.0 (which is referred to as Heda's spirit by the Grounders) inside of her neck without it killing her. When Becca returned to Earth, she sees humans approaching in hazmat suits. She tells them that she is here to help. This was the origin of the first Commander and the start of the myth behind the Nightbloods. It is still unknown how the black blood was introduced to the local population.

Overview
When a Nightblood child is discovered, they are sent to Polis to begin training for the Conclave. For each batch, or "class", of novitiates, a Conclave is held when the last Commander dies, during which the Nightbloods fight to the death. The survivor would then become the next Commander. The belief among Grounders is that the Commander's spirit (in fact the A.I. chip of A.L.I.E. 2.0) "chooses" its successor through this process, and the chip is then transferred and implanted into the neck of the new Commander. Past commanders are honored on Ascension Day.

If a Nightblood flees or refuses to participate in the Conclave, they are considered cowards and traitors to the blood and are typically hunted down.

In "Perverse Instantiation (Part 2)", Clarke, with Abby's help, used an exchange transfusion, similar to the ones done at Mount Weather, to replace her blood with Ontari's. This allowed Clarke to temporarily have the black blood and for her body to accept the Flame. However, it was only successful so long as Ontari's heart kept beating to let the blood flow into her system, requiring Abby to actually open Ontari's chest so that Murphy could literally massage her heart and keep it beating when her condition worsened.

Notable Nightbloods

 * Becca, the first commander.
 * At least two Commanders who ruled after Becca and before Lexa and members of their Conclaves.
 * Lexa's Conclave: Lexa, Luna, Luna's brother and other six novitiates.
 * Ontari's Conclave: Ontari, Aden and at least 5 other novitiates.
 * Clarke (Temporarily)

Currently, the only known living Nightblood is Luna.

Gallery
Nightbloods