Awesome game, but i feel like even in hard mode it's just too easy. With both characters, I managed to beat all difficulties on my first try with 30+ coins to spare and almost always staying at full health.
Maybe make more puzzles where you have to play around with disjointed orb clusters or use colorless orbs in clever ways in order to avoid losing health, maybe add more types of pre-placed orbs that cause bullshit, maybe add portals that teleport your orb and that you have to use to get to unreachable clusters, maybe reduce Destruction Magic's health because he doesn't need it with all them bombs, maybe make Needle more expensive and/or give it only a 50% chance to proc on any given orb per turn (i just beat the final boss in 1 round with it), maybe prevent coupons from spawning if the player already has one, maybe add enemies in the levels that do stuff based on orb elements, idk i'm just spitballing ideas.
either way great game, lots of fun