[VR-headset required, either Vive or Oculus-via-SteamVR; designed for standing-gameplay (1 square meter), but also playable while seated]

Gameplay-sample (short): https://youtu.be/JkCHGMHrgU0
Project walkthrough (long): https://youtu.be/dh7yPEAihjw

Why play hole-in-the-wall, when you can play hole-in-the-FLOOR! Surf a morphing platform down into the abyss, peering over the edge to see what shape is required next... just make sure to pull your head back into cover when the hole arrives!

Controls:
[X] Morph the platform into an "X".
[Y] Morph the platform into a "Y".
[Right-bumper] Rotation the platform 90 degrees clockwise.
[Left-bumper] Rotation the platform 90 degrees counter-clockwise.

As for the goal, there's currently no scoring mechanism, so it's currently just the personal challenge of reaching terminal velocity. :)

In addition to the source-snapshot, the full history is available at:
https://github.com/AustinSpafford/terminal_shift/tree/967953b143e101c0332379352b3bc422da8e945d

P.S. If sound is playing out of the speakers, then that appears to be a SteamVR thing, whereby in the SteamVR settings you can set which devices it should swap in and out of being the default playback-device. I absolutely wish there was a way to easily force it to the HMD's headphones, but it seems like SteamVR's generality is problematic.

P.P.S. Sadly I didn't make it in time to add more platform/hole shapes (eg. A/B/L/R). Next time a lot of Blender-eccentricities will have been learned ahead of time!

P.P.P.S. Also didn't add "hitting your head when passing through a hole" mechanics, but fortunately human-instincts seem to work pretty well for playing out the peeking-over-the-edge gameplay. :P

P.P.P.P.S. This is the first time I've done a blitz of foley recordings, but the spaghetti-snaps were amazing! Honestly they're the only major reason I checked kid-unfriendly checkbox (well, that and not wanting to encourage a fear of heights). I absolutely recommend trying it out yourself, or grabbing some of the source-audio clips for your own bone-breaking action. :)