One of the best interpretations of the theme I've seen so far, a sort of political righteousness twist on it. I played red first.
One of the first things I noticed was the floatiness of the movement. 2d platformer movement is a science that takes some iteration, but I think it is always absolutely crucial because its 99% of your gameplay. I can understand maybe wanting to encourage players to stay undergoop to get tigher movement, but any time you progress forward in an area you can't cover it in goop very quickly, so you end up playing semi on-foot. That said I love the core mechanic for red of shooting the gloops splattoon-style. I think the fact that gloops bounce off of puddles is really cool and a great idea. The level design was sufficient, though there were 1 or 2 points where the puddles bugged out and made it hard to traverse properly.
After I beat it I played blue. Blue was a little less fun for me for a couple of reasons. His main mechanic is almost strictly worse than Red's. It has lower max range, and cannot create puddles alone (which was important for good movement). His level was also a lot simpler and shorter, just a simple survival.
A really positive thing about this game was its polish in some places. Its art, music, and sound design were phenomenal for a jam game (and it looks like a 1 man band). The story was charming and the skip cutscene button was a thoughtful touch given everyone replays it once.