Damn this is one smooth browser game, you put the green/white girl platformer to shame in terms of performance. If space is not used for anything else, let it be an alternative for jumping.  Same goes for up arrow, Z is for console babbys. The pixel art looks great, but it's a shame you decided to vomit on it with those lighting effects. Collecting floating "coins" is some of the most uninspired design I've seen in a while too. Overall, it runs and looks great, but the game direction is unclear.

Good job.  I didn't expect enemies to have colliders though. Most games you pass through them or there's some knock back.

I loved the player's animation and the fireball attack variations.  The enemy seemed a bit tough due to its range and the amount of time you stand still when doing a ground attack.  It took me a while to try wall climbing because I didn't know it was a feature.  Maybe tutorialize it by forcing the player to go over a wall that's in the only way forward.