This felt really unique! Nailed the vibe and aesthetics and was super enjoyable and memorable - great job!

First of all, thank you for letting the player hold the fire button to fire, I am not a fan of button mashing in shoot 'em ups.

One thing I noticed is that the hitboxes are bigger than the sprites, so even when I saw I was dodging one of the enemies, I was hit with a ~5 pixel gap between the sprites. It's usually a good practice to keep hitboxes inside the visible sprites to prevent that. For concave sprites (like the X shaped enemies) I think that keeping the corners of the hitbox inside the sprite would be enough.

Aside from that, the controls and the gameplay feel pretty smooth. Good job!

Congrats on your first game! This is really good for a first game ever!!

You nailed the NES aesthetic, the soundtrack was great, and sound design was also spot on. The enemy patterns were actually really interesting, especially with the full 360 circle path you can take to dodge them.

As you'll see in my playthrough below, I really struggled though. I only managed to reach the first boss in one run. The main thing was not being able to predict when an enemy was going to spawn at the edge of the screen, so I got hit from behind quite a few times.

A few other minor bugs I noticed after watching my recording again: When I first played the game I start with 5 health, but then in subsequent retries I spawn with just 3 health. Also as you'll see the high score game over screen was only showing 0 points

Fun game! I feel speed mutation is a little bit difficult to control. The other mutations I tried are cool!

Good fun game, would be good to see more levels! Best time was 2:23 :) good luck in the jam