DAGON IN THE SERIES
Dagon appears in the series as a half man half fish creature that is more of a hybrid of the two. Although he does not appear human at all, he is able to pass for one when out and about with the proper clothes. Dagon was around before the Elders arrived, yet he is not an Archon. He witnessed the destruction of Atlantis personally and saw the Ruling Twins, who possessed gold and silver auras, fight and battle until Atlantis sank. Dagon serves Niccolo Macchiavelli, and has done so for four hundred years. He also has a personal vendetta against Scathach, due to the fact that she massacred his people many years ago.
In the Magician, Dagon is the driver who takes Macchiavelli around Paris. During the course of the night, Dagon takes Dee and Macchiavelli around the city on a chase, trying to catch up to the twins and Flamel. When the car is finally crashed, Macchiavelli frees Dagon from his bond of servitude, enabling him to go and attack Scathach, dragging her into the Seine River after the Nigodhogg and the final Valkyrie is defeated.
He is briefly mentioned in the Sorceress when Scathach shows up at the door of Joan and the Comte, where she mentions she fought Dagon all the way down the Seine River.
DAGON IN MYTHOLOGY
Dagon was an ancient deity of the Philistines of the Bible, considered to be the ruler of the Pantheon of Gods. It was said that he was a man from the waist up and a fish from the wrist down, although he is sometimes seen as all fish.