Don Zaloog is a villain from the first season of Yu-Gi-Oh! GX and he is the fourth of the Shadow Riders.
He was voiced by Taiten Kusunoki in the Japanese version, and by Darren Dunstan in the English version.
Don Zaloog has grey hair, that comes near his shoulders. He wears his common clothes and a golden eyepatch.
Don Zaloog tries to deceive the "Keykeepers" by making them believe he is a detective, that wants to help protect the spirit keys. However, he and his gang try to steal the keys when nobody is watching. They steal the keys, but they won't open the spirit gate. When he asks why they are not working, Chazz reveals that the keys have to be won in a duel. Don Zaloog then duels Chazz Princeton but he is easily beaten. When he is beaten the power of his shadow charm, the shadow eyepatch, stops working, and he turns back into the card he once was. He uses a "Dark Scorpion" deck.