Hey,

First of all Congrats on your Fist Game! This game is super cool and fun. A few quick tips to help you ahead in polishing this game, as well as improving in your journey -

1. If the Player stays at the centre or any other point without moving then hardly it dies as the stone never approaches that point for some reason, maybe due to randomness implemented in the logic. You can fake this by checking through a timer if the player movement stops for more than a particular time, you can spawn a stone in the same Y-axis of Player just to make him aware and move continuously. 

2. Are you using the Object Pooling concept for the Stone Spawning or you are using the regular method of creating and deleting stone outside of the screen. If you are not using the Object Pooling method then we would recommend it to use, because it's super-efficient and super performant. 

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