I had the chance to come back and play your game all the way through (What a wild boss fight, but the crown belongs to me). I thought the idea for this game was incredibly intuitive and excellent in execution. I truly love anything that has to do with Tetris and this was an amazing use of the possibilities that Tetris give you.
I did notice the collision issue on the walls where I would slow down significantly. I took a peek at the source code and saw move_and_collide. I would recommend changing to move_and_slide, which usually fixes that problem for me, you just have to pump the speed up a little for that method. It wasn’t a huge problem, but I was able to use it to cheese the chickens and first boss stage a little since they had the same slow down when colliding with a wall.
I’m curious what the combat would feel like if the pieces spawned as soon as I clicked and lasted like half a second longer. I constantly felt like I was “just” missing a killing combo and then I was on the move again. The reason I say spawn instantly is because I relied on dodging bullets more than blocking them because of the block spawn time.
Overall one of my favorite games in this jam and a joy to play and finish. It’s incredibly well polished with even some elements of level randomization (where the hat is, where the stairs are), and that was a pleasant surprise. I enjoyed the music and the sounds and found the challenge refreshing. I truly think it has a lot of potential to grow in the future. Great job!