How would I make invisibility anti-cheat

If you plan to add a client anticheat system, i would not recommend a handshake (although i might stand biased by this point as i think they are completely detectable). You’d be better off just hiding your script as deeply as you can, although nothing is foolproof. I’d recommend getting a deeper understanding of how exploits, and Luau structures such as the stack, work before attempting to make a client anticheat.