As others have said, very awesome opening cutscene! I never played Binding of Isaac but I definitely got that vibe from the intro and artstyle as well. The bossfight itself was very fun, shooting felt extremely satisfying! I think my only point of feedback is that a lot of the attacks felt like they shouldn't have been hitting me, but must have been just at the tail-end. I also wish I could have moved under the boss when he jumps up while chasing me. Those small points aside though, I still thoroughly enjoyed it, well done!