You can add a specific dummy bytes sequence around your injection so you can recognize them if ripped from your
trainer (considering the ripper is a n00b and blantantly copy/paste, huh he is a noob if he rips). My favorite is to write my nick inbetween the injection hehe.
But you shouldn't care about it, if your code gets ripped, its really easy to tell. And if a skilled reverser is interested in your code, he can grab it no matter how tough your protection is. There are several ways to do it, one like
Psych mentioned, is watching the game for alterations.
Sunbeam, that is pretty easy to bypass aswell, dump the dll from memory or even debug it live

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