Otus and Ephialtes

In Greek mythology, the Aloadae (/ˌæloʊˈeɪdiː/) or Aloads (Ancient Greek: Ἀλωάδαι Aloadai) were Otus (or Otos) (Ὦτος) and Ephialtes (Ἐφιάλτης), sons of Iphimedia, wife of Aloeus, by Poseidon, whom she induced to make her pregnant by going to the seashore and disporting herself in the surf or scooping seawater into her bosom. From Aloeus they received their patronymic, the Aloadae. They were strong and aggressive giants, growing by nine fingers every month nine fathoms tall at age nine, and only outshone in beauty by Orion.

The brothers wanted to storm Mt. Olympus and gain Artemis for Otus and Hera for Ephialtes. Their plan, or construction, of a pile of mountains atop which they would confront the gods is described differently according to the author (including Homer, Virgil, and Ovid), and occasionally changed by translators. Mount Olympus is usually said to be on the bottom mountain, with Mounts Ossa and Pelion upon Ossa as second and third, either respectively or vice versa. Homer says they were killed by Apollo before they had any beards, consistent with their being bound to columns in the Underworld by snakes, with the nymph of the Styx in the form of an owl over them.

...
Wikipedia