I read you are looking for feedback so here I go.
First must have (and I mean it): you need to set a key to restart the game, I get my hands set in the keyboard to play and I need to move each time I die to get the mouse, click restart, remove the cursor of my way and put hands in position again, it slow down the replay feature a lot and its annoying.
I passed the tutorial phase after a few tries, it is not THAT hard but its the tutorial, is supossed to be easy-peasy level to get adjusted to the controls, maybe take a look on that.
A skip tutorial button, once I knew the controls I want to get to the real challenge right away.
An autocollect diamonds feature, I mean, I can't stop to pick them, its kinda frustating blow up an enemy and see your reward being left behind.
I don't get the "buy lifes" option because, it'not like I can get 300 diamonds before wasting all my lifes unless I already mastered the game.
The rocket movement is's kinda a game breaker If I managed to get to a high spot I double jump and hit space untill I get to a new plataform, double jump, and rocket again, I kinda could skip all the levels with a bit of practice and this.
Little suggestions:
- Make the first levels slowers and get them faster gradually.
- Add some catchy music
- Make the spikes backs unharmful, the back of a spike shouldn't be able to hit me, the spiky thing is the danger, hehe