Troll (Homestuck)

Trolls are a race of aliens from the planet Alternia, which exists in a separate universe.

Biology
Trolls are known for their gray skin and candy corn colored horns which vary in shape amongst individuals of the species. They have black lips, yellow nails, and yellowish-orange eyes with grey pupils that fill in with their blood color as they age. All Trolls have black hair.

Notable features

 * Troll blood color varies on the individual level and is used to determine a Troll's social class. The twelve natural blood colors are, from lowest to highest: burgundy, bronze, yellow, lime, olive, jade, teal, cerulean, indigo, purple, violet, and fuchsia.
 * Lowblood Trolls have a very high chance of developing psionic powers, but live shorter lives and are more susceptible to injury. Psionic powers can develop in highbloods, but it's very rare.
 * Highblood Trolls have very long lives and are very resistant to injury, as well as being physically stronger to some extent. (Equius Zahhak is an edge case. Highbloods are strong, but not THAT strong.)
 * It is stated that the Limeblood caste was hunted to extinction.
 * There exists one non-natural blood caste among Trolls, only possible through genetic mutation. This mutation causes bright red blood, as seen in Humans.
 * Trolls are a violent, anger-prone conqueror species. Highblooded Trolls are generally more violent than lowbloods.
 * The highest two blood castes are amphibious.
 * There are only ever two fuchsia bloods in existence at any given time: the Empress and the Heiress to the Throne.