Really fun game! I really liked the core mechanic of the game, since it not only provided a good base for interesting levels, but it was also implemented very cleanly. Very nicely done.
A bit of feedback:
- The game does feel like it has a bit of an identity crisis in later levels. It starts off as a planned out puzzle platformer which was very appealing to me. However, continuing with the spikes and fireballs and all that, it felt kinda unnecessary. You spend all this time solving one half of a level just to misstep on a fireball and lose all your progress. It was a bit antisynergestic with the puzzle strategy aspect of the game. I also didn't find the core grow/widen/etc mechanic too helpful for dealing with such obstacles too.
Overall though, it was a very fun experience!
EDIT: So I went back and grinded out the rest of the game because I was curious how the mechanics would be used further (I stopped at level 3 before once I lost all my progress to ANOTHER FIREBALL LOL) I think my thoughts from before are just even moreso after seeing the rest of the game. I think you guys found two distinct and fun mechanics for this, a puzzle platformer, and an action platformer. Mixing the two however in the same level I feel took away from the experience. I found the purely puzzle platforming (First couple levels) and the purely action platforming (final boss battle) the most compelling levels. Levels 3 and 4 which mixed the two just made the experience frustrating. The final boss had this a bit but to a lesser extend in my opinion. I think one of the worst feelings you can get is having to repeat and go through the motions of a puzzle you already know the solution to. Especially if it takes a while to do so, and this was something present whenever you mixed the puzzle and action aspects together. Overall, I think the two concepts are both very fun on their own, but mixed together took away from the experience of an otherwise very good game.