Violating a game’s Terms of Service (ToS) is a civil matter, but in extreme cases (e.g., cheating in a game with real-money economies), developers have pursued lawsuits. Additionally, bypassing technical protections may violate the Computer Fraud and Abuse Act (CFAA) in the US.
If you are determined to experiment:
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A cleaner script that includes speed settings fly script roblox - Pastebin.com. How to Use the Script Violating a game’s Terms of Service (ToS) is