Hit credits, cool entry! For reference, my playtime was 1h20m, found Wood then Gyro, then got pretty lost lol. But found my way eventually.
First of all, the music is fantastic, the Vault theme goes absolutely crazy. I was literally hooping and hollering when the guitar solo came in. Looks like Cammy does a lot of custom Doom music, so this makes sense. The sound design is really great in general, and all the marble noises of the different materials go along way to selling each "character". And I'm never going to complain about an N64ish aesthetic.
You *nailed* the feel of the marble, I think it was the perfect amount of weight, momentum, acceleration, air control. It's a joy to control, and the hover of the Gyro is really excellent too. Unfortunately, I think a lot of that work was let down by the level design. Due to the game being a Metroidvania, the areas need to be traversable in multiple directions, which results in just a bunch of flat ground most of the time. It rarely takes advantage of the fact that you get to play as a marble. I was hoping for more slopes, ramps, maybe a halfpipe or some boost pads that accelerate you ( the boost jump things were fun! )
But honestly I think my main issue was just feeling like the entire game world needed scaled down like 33% percent or more. So much time is spent just rolling through flat space. And when you're not sure where to go, or you need to backtrack to find a barrel to switch to Lanky Kong, it does eat up a *lot* of time. It really took the wind out of my sails about 20 minutes in or so. And some water being Death and some being more level was a little confusing at first.
I generally liked the puzzles! The couple ways you can interact with any body of water was an especially cool realization. And I think each marble definitely had charm. The ****SPOILER**SPOILER**** final marble being breakable is a funny detail. ****SPOILER**SPOILER**** And they look great and animate well. I think it was a great choice to give them facets, and not be fully round, so the player can visually see direction and acceleration on the character.
Overall great work! And I think a good use of the theme. If you want to keep working on this project, I think this can be a really solid full game!