Hello! The rules are only revealed in the first three stages. From the fourth onward, they are secret, and the player must discover them through trial and error.
Thank you very much for trying it out and for the feedback. =)
Regarding Popty, I tried downloading it here, and I assume it's built on Unreal, right? I'm experiencing a temporary hardware limitation that's preventing me from playing games compiled from it... it says "A D3D11-compatible GPU (Feature Level 11.0, Shader Model 5.0) is required to run the engine." =/ If there's a web version, please let me know here, and I'll be happy to try.