First things first: I didn’t make Undertale or have anything to do with its creation. I just liked it as a player!
It’s just a simple battle scene; the only things I’ve implemented are the ability to select buttons with your controllers and dodge incoming attacks with the iconic pixelated heart (“SOUL”) from the game. You can’t win or lose, and all of the buttons do the same thing (start Toriel’s attack).
That said, it was a lot of fun to build. Working in VR is, in some ways, just like working on a normal game; I used the same tools and the same workflow… and in other ways, completely different. It’s surreal to debug objects which have a physical location relative to your desk. You also have to think about the physical scale of objects! When I imported Toriel’s sprite, I set her height to something that seemed reasonable (a bit taller than an average human), but something still seemed off in VR, she seemed a bit smaller than I imagined her from the actual game - until I realized I needed to also shrink the player. Because in Undertale, you play as a child. That one had me laughing for a while.