5. He falls to the Dark Side
This is another dark fate for Grogu, but it would be an interesting twist and holds the potential for a great villain down the road for Rey’s generation of Jedi to face off against. With Grogu not being in the sequel trilogy, something must happen for him to not be around. Maybe that thing was him going on a Dark Side-fueled killing spree after hearing about or sensing the passing of his close friend Din Djarin.
Grogu has already flashed Dark Side tendencies. We’ve seen him use the Force choke many times, especially when he thinks Mando is in danger. That is seen as a darker use of the Force, but Grogu has gone to it routinely when his emotions get the best of him. Maybe he hears about his friend’s death, boards a ship, and hunts down those who killed him. He could become so enraged when doing this and consumed with hatred that he falls to the Dark Side and begins hunting down anyone who wronged him in the past.
This could be done concurrently as the events of the sequel trilogy unfold, and when his killing spree is over he could return to Luke only to find him dead as well. This could lead him to Rey and his anger could create a tragic but interesting confrontation. If Grogu did fall to the Dark Side, he’d be a very powerful adversary to the new Jedi Order and could become a Sith almost as powerful as Sidious himself.