Zarathos

Zarathos is an angel become a demon.

Ghost Rider
After a deal with the demon overlord Mephistopheles, Johnny Blaze's soul and body are bound to Zarathos, a powerful demon, the Spirit of Vengeance, and the union of the two is known as the Ghost Rider. With the powers of Zarathos, Blaze manages to defeat Blackheart and his minions and to save Roxanne Simpson. Eager to control Zarathos, however, Blaze leaves Roxanne and begins a travel in search of redemption.

Ghost Rider: Spirit of Vengeance
Despite his efforts, Blaze is still unable to control Zarathos, always hungry for sinners' souls. The monk Moreau promises to Blaze to free him of his curse, in exchange of the Rider's help in protecting Nadya and her son Danny, two people pursued by Mephisto himself, now going under the name Roarke.

Immediately before the process of unbonding, Moreau tells Blaze the history of Zarathos: he was an angel, the Spirit of Justice, sent on Earth to protect the innocents. Mephisto, however, managed to deceive him and capture him, torturing him for eons, until Zarathos had gone completely mad. His original mission of protecting the innocents, corrupted by Hell, became a dark obsession of punishing the guilty, and he became the Spirit of Vengeance.

Despite finally being freed from his curse, Blaze accepted Zarathos once again in his body in order to save Danny, who was about to become Mephisto's new body host. Defeating the demon lord once and for all eventually seemed to cure Zarathos from his madness, and the Spirit of Justice managed to walk on Earth once again.

Character traits
Zarathos is an extremely powerful angel, and his demon powers are just as powerful, so that to make him a match to Blackheart or to Mephistopheles himself (even if the latter is defeated only in an extremely weakened form). Zarathos is able to ignite any weapon or vehicle he enters in contact with, making it a hellfire-fueled arm or means of transport. His main ability is the Penance Stare, through which he's able to consume a sinner's soul by making him live averything bad he's done to others.

Despite his great powers, Zarathos is mentally instable, consumed by the hunger of consuming souls and punishing sinners. With the time, he becomes more and more unrational and moved only by his main instinct: feeding.

Relationships

 * Johnny Blaze - Human host.
 * Carter Slade - Ex human host.
 * Mephistopheles - Enemy and master.
 * Blackheart - Enemy.
 * The Hidden - Enemies.
 * Ray Carrigan/Blackout - Enemy.

Appearances/Actors

 * Canon (2 Films)
 * Ghost Rider - No actor (Never directly named)
 * Ghost Rider: Spirit of Vengeance - Nicolas Cage (Voice only) (First appearance)

Behind the scenes
To be added

Trivia

 * In the comics, Zarathos is a pure demon, not a mad angel.
 * The comics' version of Zarathos is much more powerful than the movies' one, and deploys a wider array of powers that puts him almost on the same level of Mephistopheles.