MCU: 10 Cosmic Villains For Phase 4
4. Mister Knife
J'son was the Emperor of Spartax and in the comics universe he is the father of Guardians of the Galaxy leader Peter Quill who spent a lot of time trying to defeat the Guardians and return Peter home, to be re-educated into an heir he could be proud of.
The problem is that J'son abuses his power and has a history of murder to fit his needs. When Peter revealed this to the Spartoi people, they rose up and forced J'son into exile. J'son now needed to make a new life for himself and, not willing to give up the feeling of power he'd enjoyed for so long, he decided to use his expertise in running an Empire to build his own from scratch.
J'son built the kind of empire more suited to his personality and motives - a criminal empire. He took on the alias Mister Knife, put a bounty on Star-Lord's head and assembled a team of his own called The Slaughter Squad.
Although Peter's dad in the MCU is Ego, Mister Knife is a great enough character to stand without the links to Star-Lord. He could even begin as Emperor of Spartax and have his descent into crime be a background thread, until he becomes the main threat to the galaxy.