Answer
The answer to the question is no, Tyler Posey did not act in Avatar: The Last Airbender. Tyler Posey is an American actor who is best known for his role as Scott McCall in the MTV series Teen Wolf. Avatar: The Last Airbender is an American animated television series created by Michael Dante DiMartino and Bryan Konietzko. The series premiered on Nickelodeon in 2005 and ran for three seasons.