This was the one I was waiting for, as I was following the updates on Discord.
I really like the concept, as I'm a big fan of both metroidvanias and twin-stick shooters. The graphics serve the game well, though a bit more variation on some locations would have been nice. I like the main character, and the nice touch of shells hitting the ground.
I ran into lots of bugs however. Most of the time the weapon would simply not fire for me. I had to press left click repeatedly until the weapon would eventually start to fire, then holding down the button would have it fire non-stop without issues. Coin collection was also buggy. I would collect coins but the number wouldn't go up. And the music, while somewhat fitting, was too repetitive.
With a bit of polishing and sorting out the bugs this could be a great game. Well done!