Eridan

Eridan Ampora, also known by his Trollian handle caligulasAquarium, is one of the sea dwelling trolls. His associated zodiac sign is Aquarius (♒), and his horns are wavy which could possibly represent his associated symbol.

His name is derived from the river Eridanos, which was poured onto the Earth by Aquarius in Greek myth (or possibly from the constellation Eridanus), and the amphora, a type of Greek vessel for carrying liquids which is often seen in depictions of Aquarius. If his first name is read backwards, it reads "Nadire" (A nadir is "the lowest point; point of greatest adversity or despair"), though this could be coincidence.

"Eridan" could also come from the star "Eridana," or the constellation "Eridanus", or even the Eridanus Supervoid, a region in the sky almost as cold as absolute zero. "Ampora" means protection which could be ironic with him doing the exact opposite. When you shorten his name to the first and last syllables, it sounds somewhat like Harry Potter (Eri' 'Pora,) although that could be coincidence. It also resembles the word eradicate, possibly referencing his genocidal tendencies. His Trollian handle is presumably taken from Troll Caligula.