League of Legends maker Riot Games is now combating cheating in the game with legal tools as well as technological tools. In a lawsuit filed in the US District Court for Central California (and obtained by The Rift Herald), Riot argues that popular cheating tool LeagueSharp (a.k.a L#) has "cause[d] serious harm to Riot and its community" by illegally circumventing the game's DRM and breaking the Riot's Terms of Use.

The lawsuit accuses a trio of German hackers—Matthias "Jodusmame" Oltmann, Stefan "0hm" Stefan Delgato, and Tyrone Tom "Beaving" Pauer—of being behind a Peruvian shell company that publishes LeagueSharp. The software, which costs between $15 and $50 a month, is advertised as "easy, efficient, gamebreaking." Riot, on the other hand, calls it "a product that is specifically designed to enable a subset of LoL players who do not wish to play fair to gain substantial unfair advantages over legitimate players (in other words, to cheat)" in its lawsuit.

In addition to making and distributing LeagueSharp, Riot accuses the hackers of conducting "repeated attacks on Riot’s game servers" and advising players on how to avoid detection. What's more, Riot alleges, the hackers or their associates "disseminated personal and non-public information about a Riot employee, threatened that employee, and posted offensive comments on the employee’s social media."

Attempts to resolve the matter without litigation have fallen on deaf ears, Riot says.

The lawsuit goes to great lengths to explain how crucial a sense of "fair play" is to the maintenance of LoL's massive community of players and the significant expense and effort Riot undertakes to prevent cheating. "By enabling some LoL players to cheat in the game or to automate their performance, L# disrupts (and threatens to destroy) Riot’s carefully crafted gameplay, and ruins the game experience for players that take the game seriously and who wish to play fair," the company writes.

That's a fine argument, but what makes it legally actionable? Riot says this anti-cheat technology violates the DMCA's provisions regarding anti-circumvention technology, and it also violates the Terms of Use clickwrap contract all players agree to when making an LoL account. Riot also says LeagueSharp contravenes a California statute regarding "unfair competition" through "oppression, fraud or malice."

This is far from the first time a game maker has used the legal system to go after cheating services. Back in 2009, Blizzard successfully used the DMCA to shut down Glider, a popular World of Warcraft bot service. More recently, Blizzard has filed a lawsuit against Buddy Bot, a popular Overwatch cheating tool. And last month, Epic Games sued the creator of "the world's most powerful hack for Paragon," using similar legal reasoning.

Riot is seeking restitution of "unlawful proceeds" generated by L# sales, statutory damages, and the completely shutdown of L#'s web site and online distribution. The defendants have 21 days to respond to the Riot's suit.