Professional League of Legends players cannot stream Hearthstone, World of Warcraft, StarCraft II, Dota 2, and World of Tanks, Riot Games has decreed.

League of Legends players who wish to compete in Season 4 of the Championship Series must sign a contract that precludes them from streaming titles Riot Games deems to be in competition with its popular MOBA.

In response to community backlash, Riot eSports manager Whalen 'RiotMagus' Rozelle took to Reddit, saying the company wants League of Legends to be a legitimate sport.

“There are some cool things that come from that (salaried professional athletes, legitimate revenue streams, visas, Staples Center), but there’s also a lot of structural work that needs to be done to ensure a true professional setting.”

“We recognize there may be some differences of opinion in the perception of pro players’ streams. In the past, pro gamers only had to worry about their personal brands when streaming and, at most, may have had to worry about not using the wrong brand of keyboard to keep their sponsor happy. Now, however, these guys are professionals contracted to a professional sports league. When they’re streaming to 50,000 fans, they’re also representing the sport itself.”

“I can’t stress enough how these guys in the LCS are on the road to being real, legitimate athletes. This is new territory for a lot of teams (especially in esports), because the transition goes from being a group of talented individuals to being real icons of a sport and a league. Similarly, you probably wouldn’t see an NFL player promoting Arena Football or a Nike-sponsored player wearing Reebok on camera. Pro players are free to play whatever games they want – we’re simply asking them to keep in mind that, on-stream, they’re the face of competitive League of Legends.”

The full list of games Riot has blacklisted:

Awesomenauts, Bloodlines Champions, Crasher, Dawngate, Demigod, Dota 2, Fat Princess, Guardians of Middle-Earth, Hearthstone, Heroes of Newerth, Infinite Crisis, Land of Chaos Online, Monday Night Combat, Realm of the Titans, Rise of Immortals, Sins of a Dark Age, SMITE, Solstice Arena, StarCraft 2, Warhammer Online: Wrath of Heroes, Warlocks, World of Warcraft, World of Tanks, and World of Warplanes.