Let's assume i have created a game, and then created ERC tokens (Example swords) so the player must buy a token to be able to play the game.
What if someone creates similar tokens in his wallet and injects them into my game as if they are bought from my tokens store
Indeed, there are no way to create token which will be similar with your created token because can't copy your smart contract address which is already under your control. So who guy how will make same token from individual contract addresses. Although you have to know all about of security issue to protect your tokens also game. Otherwise here hacker will try to find technical error. What if someone creates similar tokens in his wallet and injects them into my game as if they are bought from my tokens store