That's obvious, dude. Aku destroyed all the time portals. So he likely sees no real point in trying to defeat him. As he even says in the opening, "all hope is lost." So he just wanders around using whatever weapons he has rescuing people from Aku's forces because even if he is in a hopeless situation, he's still a chronic hero who can't stand idly by while innocent people are threatened.
Second episode. Aku's therapy session with himself.
They are setting up the final battle. Ashi is involuntarily rallying all the characters Jack helped in the first 4 seasons and they made a good job by giving a quick reminder of who they were and how they are involved with Jack. There's plenty of other characters out there that will likely reappear to help Jack, like the seamen, talking dogs, the "jump good" guy, etc, but this episode already established that they all are going to be in the final confrontation.
Wasn't he kind of banished to the pit when he was defeated by Jack?, interesting that Aku would give him a second chance or probably doesn't care what his subjects do anymore and let them loose. This might also mean we might have all them back for the final confrontation, which already sounds exciting.
He was (seemingly) killed, actually. Aku has him trapped in some glass skull thingy, and he asks for a second chance. Aku seems to consider it for a moment but ultimately decides not to and crushes him in his hand.
