Answer
Martial arts are a recurring theme in characters voiced by James Sie. He has portrayed characters such as "Master Splinter" in "Teenage Mutant Ninja Turtles," "Khan" in "Star Trek: The Next Generation," and "Sensei Wu" in "Ninjago." Sie's characters often possess wisdom and skill associated with martial arts, contributing to his reputation as a prominent voice actor for Asian and martial arts-related roles in animation and video games.