How do I experience this?
This is a WebXR experience so it should (in theorey) work on any headset that has 6DoF controllers, however I could only get it reliably working in Firefox on the PC.

What did you use to make it?
Unity (of course) and the WebXR export template from Mozilla.
All models were made in Blender, textures created in FilterForge, Sound effects are from the Cafofo Monster Sound Pack, and the background is from AllSky free HDRI pack.