Hmm, quite the interesting little game! It's pretty shallow right now and could use a lot of polish and a better definition of what it's end goal is (how long does the game go and how does it evolve during play and what is the player striving to do), but nevertheless I felt like the game at its core was very fun and satisfying to play even without these aspects yet!
It's definitely a little clunky in some respects. I had no idea that you could double-jump, meaning I was quite stumped at how to get past the tall wall at first, and I was annoyed that if you let go of the slide button while in a narrow tunnel you get killed immediately, instead of the game more logically just keeping you sliding until you get out of the tunnel and automatically standing up then. There are also some weird glitches here and there like bullets sometimes making explosions when they hit a wall and sometimes not.
Finally, I was a bit annoyed at the money with how it doesn't magnetize to you and also has weird physics and collisions tied to them, which meant that it would just scatter randomly and be incredibly unfair/hard to pick up. Speaking of money, I was also curious why the game has you buy the heart pack instead of it just happening automatically when you get enough money, like getting a 1-up in Mario or Sonic when you get enough coins/rings: part of me is worried it is there to create some sort of proof of concept for a gross microtransaction system where you can buy lives with real money and I'd prefer that not be the case and just be my silly paranoia, please.
Certainly has a lot of potential in my book and has a great start by focusing on a satisfying and fun feel to the core gameplay: looking forward to updates!