Not too bad. Needs improvement.
I started out thinking it was kind of shit, but I found myself continuing to play anyway and I got through to the end. The controls are fairly simple, the gameplay's unoriginal but it works.
One improvement I would have made would be Mario-style bouncing when you land on an enemy. Another would be, with the final boss, the rhythm you're supposed to use when alternating left and right after getting grabbed doesn't make much sense. I immediately went as quickly as I could, which didn't work, so eventually I just tried going slower, which did work. But it still didn't really match up with the flashing arrows, so they were kind of misleading.
Good effort, I guess.