This market resolves YES, if:

• Before 2025, Elon Musk and Mark Zuckerberg agree to fight eachother in some kind of combat sport (Boxing, Kickboxing, any Martial art, heck even Wrestling would count)

• Said fight actually happens before 2025

• Clear rules governing who counts as the winner of the fight are established and communicated to the public

• Mark Zuckerberg wins the fight

If the fight doesn't happen before the resolution date, or is delayed past it, this resolves N/A. They have to agree to it and actually have the fight for this to resolve YES or NO.

If the fight goes through and Elon wins, this resolves NO. If the fight goes through and it's a tie, this resolves NO. If they agree to a fight, but it's not in a formal setting and they just drunkenly beat the tar out of eachother outside of a bar some random night, regardless of who has a better showing this would resolve N/A because the correct kind of fight didn't happen.