Krios

Krios (Ancient Greek: Κρεῖος), also known as Crius and Kreios, is a son of Ouranos (the sky) and Gaia (the earth). He is also the grandfather of Hecate the godess of magic. He is also the Titan of Stars and Constellations,he is associated with the constellation Aries. This was the first of the constellations, whose springtime rising marked the start of the new year in the ancient Greek calendar. He is known as the Lord of the South and as "The Ram", which explains the ram horns on his helmet in The Last Olympian. Krios sides with Kronos in the Second Olympian War. While Kronos was being defeated, Jason and his allies from the Roman Camp defeated Krios and destroy Mount Othryrs.

History
The least individualized among the Titans, he was overthrown in the Titanomachy.

Consorting with Eurybia, daughter of Earth Gaia and also Sea Pontus, he fathered Astraios and Pallas as well as Perses. The joining of Astraios with Eos, the Dawn, brought forth Eosphoros, the other Stars and the Winds.

Krios was inexorably involved in the eleven-year-long war between the Olympian gods and Titans, however without any specific part to play. When the war was lost, Krios was banished along with the others to Tartarus the darkest part of the underworld.

In Greek mythology, Krios was one of the Titans in the list given in Hesiod's Theogony, a son of Ouranos and Gaia. The least individualized among them, he was overthrown in the Titanomachy. M.L. West has suggested how Hesiod filled out the complement of Titans from the core group, adding three figures from the archaic tradition of Delphi, Coeus, Phoebe, whose name Apollo assumed with the oracle, and Themis. Among possible further interpolations among the Titans was Krios, whose interest for Hesiod was as the father of Perses and grandfather of Hecate, for whom Hesiod is an "enthusiastic evangelist".

Appearance
Krios was said by Percy to be wearing a set of ram's horns along with armour with stars on it when he saw him in a dream.

The Last Olympian
Krios first appeared in The Last Olympian. He is first shown at Mount Othrys watching the scenes of wars next to Hyperion. He talks to Hyperion about the war and then starts to pout due to Hyperion being able to burst into fire and he having to have ram horns and being Lord of the South. As mentioned in The Lost Hero Krios was "destroyed" in this book (according to Jason).

The Lost Hero
Krios was mentioned in The Lost Hero, where it is revealed that he was "destroyed" by Jason in the Roman attack at Mount Othrys. Jason says this after he rescued Juno/Hera from Gaia's prison in the the battle against Porphyrion and in the council.