The idea behind this is great. I love the random switching aspect of the platforming. Never knowing if it is going to happen at an inopportune time really adds some nice tension.

The art is beautiful in its simplicity and very elegant. Well done on that front.

I had some issues with the collision detection, with the character(s) getting stuck on the platforms' slightly irregular corners.

Interesting concept. I feel like it was missing some meat. More mechanics or a story might be nice.

This is a nice start, but I think some design improvements would make this game really great; heres some things to consider:

* the red/sun form feels pretty bland in comparison to the blue/moon form, since the moon form has darkened view, revesed controls, higher jump, and can see hidden passages, but the sun form can only run and jump. Maybe the sun form could be given some cool abilities too?

* I reached a dead end in the underground section where I couldn't jump high enough as the sun form, but even after waiting a long time I didn't turn into the moon form, so I was stuck.

* As the moon form, you can't see where you are jumping down to in some situations. This causes the player to make a blind jump and hope they don't fall into a pit.

* since running and jumping is the bread-and-butter of the game, the bug where you stop jumping if you bump a wall mid-air is pretty distracting.

I liked the music and level ideas, River Styx was cool :)

Cool concept and fun gameplay.  With some more polish and tighter controls his could be pretty awesome.

Cool concept, but my OCD was triggered every time the tiles weren't perfectly arranged. Not to worry though, it's a jam game after all ;)

Really cool music and art style, the controls need a little more polish, and maybe a wider FOV is hard to see where to go, nice game keep it up.