In Greek mythology, Otus was one of the Aloadae, the twin giants of Thessaly, his brother being Ephialtes. The pair were sons of Princess Iphimedia, wife of Aloeus, by the god Poseidon, whom she induced to make her pregnant; from Aloeus, sometimes considered their real father, they took the patronymic "Aloadae." Famed for their enormous size and aggression, the twins grew at a prodigious rate and notoriously plotted to storm Mount Olympus and war against the gods. They ultimately perished on Naxos, killing each other while hunting a deer that was in fact the disguised goddess Artemis.
Adapted from Wikipedia, "Aloadae" · CC BY-SA 4.0
I.Family
Otus and his twin brother Ephialtes were the Aloadae, Thessalian sons of Princess Iphimedia, the wife of Aloeus. Their true father was the god Poseidon, whom Iphimedia induced to make her pregnant by going to the seashore and disporting herself in the surf, or scooping seawater into her bosom. From Aloeus, who was sometimes named as their real father, they received the patronymic by which they are best known, the Aloadae.
The twins had a sister, Pancratis (also called Pancrato), who was renowned for her great beauty. Other siblings named in the tradition include Elate and Platanus.
II.Mythology
The Aloads were strong and aggressive giants who grew by nine fingers every month. By the age of nine they stood nine fathoms tall, and in beauty they were said to be surpassed only by Orion.
III.War with the gods
The brothers plotted to assault Mount Olympus and to war against the gods, Otus seeking the goddess Artemis as his bride and Ephialtes seeking Hera. Their strategy was to build a pile of mountains atop which they could confront the gods, typically described as stacking Mount Ossa and Mount Pelion upon Olympus to scale the heavens.
Homer reports that Apollo destroyed the two before their beards had grown. In another account the brothers captured the war god Ares, confining him in a bronze jar for thirteen months, until Hermes rescued him after the twins' stepmother Eriboea revealed where he was held.
The Aloadae ultimately met their end on the island of Naxos. There Artemis changed herself into a doe and leapt between them; the twins, unwilling to let the deer escape, hurled their spears and, missing it, struck and killed one another simultaneously.
IV.Other stories
According to Diodorus Siculus, the Aloadae were Thessalian heroes sent by their father to recover their mother and sister, who had been carried off by Thracians. After defeating the Thracians on Naxos they settled there as rulers, but in time fell into a quarrel and killed one another.
Pausanias records that the Aloadae were the first of all men to worship the Muses on Mount Helicon, and that they founded cities, among them Ascra, as well as a settlement on Naxos. In this strand of tradition they appear as founders and benefactors rather than as enemies of the gods.
V.Paleontology
The dinosaur ichnogenus Otozoum — a name applied to fossilized trackways — was named after Otus, in reference to the Aload's legendary great size.