Percy Jackson and the Olympians: Legends

Deimos has black straight hair, brown eyes, a black beard, and fair skin. His left eye is blinded, marked with a red scar across the left side of his face. Deimos' birthmark seemed to glow orange instead of red and looked more "corrupted", possibly due to his time spent in the Domain of Death. He also wears ancient Spartan combat armor.

Deimos is known to be more aggressive than his brother, Phobos. Despite his cold behavior towards Clarisse, Deimos isn't all that bad, as he accepted his other half-sister Piper's request for help. However, this could be because Piper is a child of his mother, and so he isn't as aggressive with her as he would be with a child of Ares.

Along with his twin brother Phobos, Deimos would often accompanies Ares in battle. During the fall of Troy, Deimos inflicted bloodshed and terror in the war with Phobos, his aunt Enyo, and Eris. Achilles later depicted the aforementioned gods in his shield. Years later, angry that their sister Clarisse La Rue was allowed to ride in Ares' chariot because they usually use the chariot, Phobos and Deimos decide to steal it from her. They then hide it in the Staten Island Zoo, and use it as bait to catch their sister and Percy Jackson. Deimos fights Percy but is defeated and disappeared. Deimos changed his appearance to match Ares in order to scare Clarisse, but he disappeared again after she overcame her fear.