The legality of cheating in video games has already been challenged in a court of law.
You see, Nintendo didn't want people to cheat. Fearing it would lower the financial value of their games if you can beat them in just a few minutes.
It was argued in court that a video game is no different than a book. If you want to read the end of the book, skip to your favorite chapter or skim quickly through a boring part you can. The conclusion is the game is yours to enjoy in anyway you want. Nobody can tell you how to play your game.
There's an interesting and short documentary about the legal history of cheating in video games by the gaming historian.
Also it doesn't matter what the TOS says.
TOS is not legally
Good news: another federal judge has ruled that violating a website
terms of service is not a crime. But there's bad news, too — the court
also found that bypassing technical or code-based barriers intended to
limit access to or uses of a website may violate California's computer
However, I've read you can be sued for breach of contract, if the site can prove any damages based on your cheating. I found that answer here on Law.SE and they didn't provide a source so I can't verify if it's true.