A Japanese prince to the Emperor after the Emperor banished Aku to the Pit of Hate. As a young boy, he left his kingdom once Aku enslaved it. The boy grew older and encountered Aku. The prince was sent to the distant future and met a trio of street aliens that nicknamed him "Jack" as in friend. He adopted it as his name. Jack realized he got sent to the distant future and has encountered dozens of solutions to go back to the past and stop Aku from creating a dystopian future.
Season 5
Fifty years have passed since the last time portal was destroyed by Aku. Jack gained a beard and didn't age.