Hecate is the minor goddess of the Mist, magic, crossroads, nightmares, ghosts and more. She is typically considered one of the Chthonic deities, or Underworld gods. Offerings were left for her at crossroads on certain days, and her protections invoked on doorways. She is one of the more imposing gods, with it once being said that even Zeus was scared of her power.

Hecate plays a leading role in the second book of the Senior Year section of the main series: Wrath of the Triple Goddess. We see her at her most powerful and most mercurial, changing from fury to whimsical amusement in seconds. In other books, she appears as mysterious and leaning towards benevolent, such as her tutoring of Hazel Levesque in the Heroes of Olympus books or her intervention in Son of Magic.

Hecate shows a fondness for mortals with clearsight, the ability to see through the Mist, guiding them through their visions. She is often accompanied by a black dog, Hecuba (ex-queen of Troy), and a polecat, Gale (one of her old priestesses).

Hecate sided with the Olympians in the first Titanomachy (titan war) where she earned a place of honour amongst the gods. She was a second-generation titan herself, betraying her family to support the new gods.

In the first Gigantomachy (giant war), she defeated Clytius with the help of Dionysus and Heracles, lighting the giant’s hair on fire.

She aided the search for Persephone when Hades took her, lighting the way with her torches.

In the second Titanomachy, she sided with Kronos. This was because she was tired of her children being ignored, as many other minor deities were.

In the second Gigantomachy, she killed Clytius again with the help of Hazel in House of Hades.

-Zeus, Poseidon and Hades gave her power over their three spheres in some myths.
-In other myths, Hecate is a virgin goddess, giving birth similarly to Athena.
-Her Roman name, Trivia, refers to knowledge that she presided over, and now just means assorted general knowledge.
-She appears in Macbeth.

Information from Riordan Wiki - Hecate

Written by Invern Solstorn