Twins

Some gods, Titans, and demigods are twins. Here are them:

Titans

 * Prometheus & Epimetheus
 * Helios & Selene

Gods

 * Apollo & Artemis - Twin
 * Calliope, Clio, Melpomene, Erato, Euterpe, Polyhymnia, Terpsichore, Thalia, & Urania
 * Aglaia, Euphrosyne, & Thaleia
 * Clotho, Atropos, & Lachesis
 * Dike, Eunomia, & Eirene
 * Deimos & Phobos
 * Alexiares & Anicetus
 * Pegasus & Chrysaor
 * Boreas, Notus, Zephyrus, & Eurus
 * Zethes & Calais