Incredible game, absolutely polished little package. I've already sunk hours into it and done all there is to do right now. The animations and sprites are all great, and looove the synergy between different powerups and character states and the excitement of uncovering them by accident.
If you aren't used to fixed vertical shooters my big advice is to always keep your hitbox(es) in your eyesight. Also the Anti-Matter cakes are a really valuable resource, especially if you're starting a level at a huge size and can't hit immobile right away - especially as Phoebe. There's a learning curve but I found it satisfying.
Really curious what's planned for the Campaign and looking forward to the next update! I'm probably gonna try making a custom character or two as well, thank you for including that feature!