I saw that on Itch.io and somehow didn't connect that it was a Clickteam thing. It's interesting that they're running two competitions at the same time.
I'm guessing this one may just result in a bunch of generic action platformers with bullet-time / variable gravity etc, but hopefully some people will come up with something a little more inventive.
It's a shame Fusion doesn't really do 3D, or there'd be potential for playing around with perspective and impossible geometry, like Polysphere or Monument Valley (maybe with a bit of Fez thrown in).
It's funny noone made those games sooner. I always thought a game like Polysphere would be fun, since seeing the Channel 4 idents on TV years ago. Likewise, I always thought a game like Monument Valley would be fun, since seeing Escher drawings. I'm sure I wasn't the only one...
Also if you liked the Matrix movies or want some inspiration, try the 2019 Russian movie "Coma" - it's visually stunning, and has plenty of "mind-bending" stuff going on (it's a bit of an Inception rip-off too, but better).
Yeah, I think I actually have it, but never bothered to try it properly. It didn't seem to catch on (much like Jamagic) and it looks like it's been kind of abandoned now.
I was thinking more for someone else anyway. I don't really have the time or inclination for a gamejam, although the 30 minute one is certainly intriguing - I just can't think of a good concept for that. And I should be trying to focus on my little roguelite...