Alton D'Yer is a Green Rider. He is described as young man with sandy hair and a square chin. His horse is Night Hawk, a tall, black gelding with white socks and a blaze. His brooch has the ability to generate a shield.
In Green Rider Alton is one of the few in Sacor City who is friendly to Karigan. He is from an aristocratic family and is not allowed to go on rides like the other Green Riders. He feels that he is not a true Green Rider and feels guilty when he stays behind while his comrades are injured or killed. While escorting Karigan to the river on her way home, Alton sees the king and his hunting party attacked by groundmites. He and Karigan fight against the Eletian Shawdell and Alton is wounded by an arrow. At the end of the book, he has returned home to attempt to repair the breach in the D'Yer wall.
First Rider's CallEdit
While attempting to repair the breached Wall, Alton is attacked and presumed dead. He hallucinates that he sees Karigan and unwittingly brings further damage to the wall.
High King's TombEdit
Alton is unwell and the D'Yer Wall will not allow him access. He struggles with his feelings for Karigan, but at the end of the book writes a reply to her long-unread letter.