Suggested by iKnowledge Luke Skywalker is a powerful Jedi. In fact it is fair to say that he is one of the strongest Jedi to ever pick up a Lightsaber. Kumonga is a powerful Kaiju, but he isn’t ready to deal with power on that level. Luke can use his force abilities to keep Kumonga at bay or to assist him in dodging any possible attacks. From there a few swings should quickly seal the deal. As formidable as Kumonga is, he simply isn’t ready to deal with such a versatile opponent. Luke Skywalker wins.
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Considering how powerful Luke was in Legends, He should defeat Kumonga, for he has faced too many beings to let Kumonga defeat him. The only Kumonga has going for him is radiation, since he faces Godzilla. As a bonus, I could see Luke using defeating Kumonga as extra credit for all his Jedi students to try and defeat.
Agreed, I don’t think Kumonga would last long here. Luke’s force abilities are just too much for him. Kumonga definitely would make for a classic student project