Hello,
Last weekend I streamed this game. Overall, I actually enjoyed this one quite a bit (which was a nice change of pace, since all night I had been playing some janky games.)
I think it is an uphill battle as a 2D sidescrolling action platformer since they are a dime-a-dozen, but I do see the potential here. The concept of bouncing the hammer is both cool and satisfying and allows for natural skill improvement within the player as they become more and more familiar with when and how to utilize the hammer's bounces. This is by far the coolest part of the game (which makes sense since that's what the marketing is all about.)
I do wish the sound effects and visual effects were polished up a little bit. For such a cool (and the bread and butter) mechanic of the game, the execution of this mechanic is satisfying, but the visuals - and especially the sound design - is not as satisfying. I wish there were some really meaty thumps, bumps, and cracks when thrown and bouncing off walls and objects. But that's just small potatoes in an otherwise great game.
I think my 2 biggest frustrations with this game are:
1) The heart mechanic is really punishing and frustrating. When you are hit, you drop your heart. A timer begins to tick down on the heart, and the timer itself begins ticking down quickly. It also tends to bounce wildly away from the player and can be knocked away by not only enemies but also your very own hammer. It seemed like any time I dropped the heart, it was impossible to pick it back up again. I feel like the heart should move much slower and the hammer should either be able to retrieve the heart for you or at the very least stop the heart's momentum to make it easier to retrieve.
2) Holy hell the first boss of the game is a lot to have to manage being only the third level in the game. It's asking the players to manage where they are throwing the hammer (a mechanic that they just started learning 2 short levels ago) by either throwing it at the boss or clearing the falling tetris pieces above. You are having to manage your position, but also dealing with the roots that grow up from the ground, and just when you think you are getting to grips managing the falling tetris pieces, movement and jumping, roots, and damaging the boss, suddenly the boss changes phase, giving you a whole new set of things to learn and come to grips with, which only later becomes yet another phase. This boss really feels like something that should have been near the end game, this challenge bump was absolutely insane.
If you'd like to watch my experience with your game, I've linked the archive below. You can click the timestamps to jump to when I start playing your game.