Out of Python, Construct and Rust, Rust is my favourite, as it is the only one that does not punish me for the way character controls ¦3
I guess, these controls are the hardest boss of this game, with nanosecond walk moves you half the map, and, at the same time, each jump keeps you in the air for hours. If that feeling of despair is what you wanted, you made it all well!
The art fits well with the game. All the bosses felt unique in many ways, from how they look to how they interact with the arena. Good job!