So basically, in the game that I am working on, from killing your opponent you will get 5 Cash. My idea is if you have double cash gamepass, you will get 5 Cash more, so 10. Any idea how to do this?
Check if the player has the double cash gamepass, and if he does then give 10 cash instead of 5. By personally spending 5 seconds to utilize http://google.com, I found you what you need: https://developer.roblox.com/en-us/api-reference/function/MarketplaceService/UserOwnsGamePassAsync