In Greek mythology, the Aloadae were Otus and Ephialtes or Ephialtis, sons of Iphimidea and Aloeus. They were strong and aggressive giants, fifty-four feet tall at age nine.

The brothers at one point wanted to storm Mt. Olympus. They piled Mt. Ossa atop Mt. Pelion but were killed by Apollo.

According to another version of the siege, they managed to kidnap Ares and hold him in a jar for thirteen months. He was only released when Artemis offered to sleep with Otus. This made Ephialtes envious and the pair fought. Artemis changed herself into a doe and jumped between them. The Aloadae, not wanting her to get away, threw their spears and killed each other.

Some considered them beneficient bringers of civilization, founding cities and teaching culture to humanity. Specifically in Naxos and Boeotian Ascra , two cities they founded, the pair were intensely worshipped.

Ephialtes (lit. "he who jumps upon") is also the Greek word for "nightmare," and Ephialtes was sometimes considered the demon of nightmares.