I personally think that this game is good, but I think it should follow more of the early game spore idea. If you somehow implemented some sort of variations that the player could choose for the design of the cloud. It might also help if you looked at ship customization in Upgrade Complete for an idea of what people find addicting these days. The overall thing I think you should start with though, is making things able to be customized.
This game has an excellent concept! An improvement to add would be other shapes. It would bring in more players and make it so it could be easier or harder! I hope that this game helps you learn how to create a successful game.
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