This is a promo video for a wrestler who's part of New Japan Pro Wrestling named Kenny Omega, he actually got Toby Fox and Temmie Chang to help make this video with him, and it also uses a sample from RichardEB's cover of the Asgore boss theme.
After seeing this I'm actually now interested in the idea of a wrestling themed RPG (like take that one chapter from Paper Mario: The Thousand Year Door but make an entire game like that).