The Emperor of Darkest Yin is the former (most likely first) Shadow Dragon and the elder brother of Yin Wi. He is a villain in Legend of the Dragon. He was the previous shadow dragon prior to Ling before being locked up and he also has a younger sister named Yin-Wi.
He is the number one enemy of Ang and Lingwho are the Golden Dragon Twins, and he will do anything in his power to destroy them and the rest of the non-Shadow Guardians, as well as any of his own who defy him, such as K Ho and Tex.
The Emperor was restored back to life by The Zodiac Master and Ling by collecting four Power Bands (Shadow Snake, Shadow Ram, Shadow Ox and light Rooster), in the final episode of season one. He then proceeded to breathe life into his terracotta army, and told Ling to kill Ang and bring back his Power Band, only to get very angry when he found the Shadow Dragon Band had been destroyed, converted into another Golden Dragon Power Band.