I liked it. It reminded me of Flappy Bird, except vertical instead of horizontal. The birds were very cute. I do wish there were more platforms along the route because they acted as nice checkpoints so that falling didn't feel so punishing. Falling felt a bit punishing as well because I couldn't see a way to catch myself. Though that might be the unstable part of the game coming into play. I also feel like if you removed the ninja elements it could also work as a sort of "canary in a cole mine" situation. I say that as a compliment by the way. I think it's good when it's the game play that sells a game jam's theme, rather than the art or overall aesthetic.