I wanted to add a sound to the easter egg, but I wanted to make sure I didn't break any jam rules since that audio is from another game, I wouldn't have rights to use it. When it comes to level unlocking, I agree. Having to beat the previous levels to unlock the next ones would definitely be better. Though I'm not sure about having a limited time because people with different skill levels might have issues with that, it would be hard to balance. The point of the timer is more so for adding replayability by promoting doing the levels in a faster time. Thanks for the feedback!