The Shadow Thief

History
Since a young age, Liu was trained by the Shadow Guild, a millennia old Guild of thieves, assassins and spies trained by the Legendary Shadow Masters. The Guild was known for having strict rules and traditions, and their goals were to help the weak and protect the oppressed. Liu became known as the Shadow Thief and an important part of the Shadow Guild, one of the Seven Shadow Masters.

When Shang-Tsei was on his rise to power, before the events of the first episode, the Shadow Guild decided to throw an attack on the Dragon Clan to prevent a disaster, but unknown to them was that Sinistra had recently joined forces with Shang-Tsei, and this lead to their failure; all of the Shadow Masters were killed, leaving only Liu alive. Shadow Guild traditions wanted that a defeated member of the Guild would swear eternal service to whomever defeated them. Liu then became servant of Shang-Tsei as he appeared in the episode "The Shadow Thief", but when the Warriors of Chronos dissuade him from serving Shang-Tsei at the episode, Liu remembers the children he must take care of, the ones from the Guild that were then abandoned since the Guild was disbanded, and Liu decided to go against Guild rules and work on his own account, and do anything that was better for the children.

In the parallel dimension Luna visits in the "Luna and the Warriors of Chronos" story arc, the Shadow Guild was never defeated by Shang-Tsei, and Liu appears with his fellow Shadow Masters to help Luna overthrow Shang-Tsei.