I like the limited palette, makes the eyes and power-ups really pop. The background could stand to be a bit brighter overall, I ended up running into some ground spikes before I could see them.
There are some clunkiness/polishing issues I ran into while playing. You have player control still while the title sequence is going, so I managed to kill myself before the game started and couldn’t get into the actual game at first. After I waited for the title to run fully though, I got in fine.
On a 1920x1080 monitor, your character seems to be stuffed away in the top left corner. I can’t tell if that’s a bug or a design choice, but it’s a bit disorienting. You also can’t exit the game from inside the application, which is fullscreen so you can’t get to the [x] button either. Alt+f4 is not the most desirable way to end a game.
Overall good effort though!