The Ghost of Zen Tuo is the villain in "Mystery Mask Mix-Up", an episode of Scooby-Doo, Where Are You!. He was the disguise of A. Fong, an oriental art dealer and the leader of an international smuggling ring. His two henchmen were also disguised as Zen Tuo's zombie minions. They did this to scare away people that were curious about the haunted Buddhist temple that was a base for his smuggling operation.
Zen Tuo, who reportedly was a Chinese warlord, was greatly obsessed with getting his mask back (mainly because Mr. Fong was more concerned about the recording tape message inside the mask) and keeping his temple a secret (as it acts as a base of operations for Mr. Fong and his henchmen).
He had little patience over repetitive acts, as he snapped Shaggy's stick in half after Shaggy tried to prevent him from crossing over lines he drew repeatedly. He also had no concern over destroying rooms in his temple, as when he tried to kill Shaggy and Scooby with fireworks in a storeroom, Zen Tuo told them that he and his men "will build a new storeroom".