In January 2014, longtime game designer Michael Molinari was testing a prototype of his studio's new multiplayer project. Choice Chamber, built for the massively popular streaming platform Twitch, promised a new kind of audience participation. Tens of thousands of people can watch a game on Twitch, but in an ordinary game, that's all they can do. In Choice Chamber, though, viewers could control the game's power-ups, weapons, and terrain, either helping or challenging the player as they jumped and slashed through it. "Of course, I'm not very popular, so I had maybe 10 people play it," he says. "Two weeks later, Twitch Plays Pokemon came out."

"I lost some sleep over it."

Twitch Plays Pokemon was part game, part social experiment. An emulated version of Pokemon Red translated chat-window commands into button presses, creating a chaotic, massively multiplayer version of Pokemon that spawned its own subculture, including a series of tongue-in-cheek religions, and drew up to 120,000 viewers at a time. Its anonymous designer smoothed out the mechanics, adding an optional "democracy" mode that accepted only the most popular commands, and the game was completed after slightly over two weeks on March 1st. By that time, its popularity had temporarily crippled the Twitch network, and viewers on other channels were playing chat-based versions of Zelda, Street Fighter, and Super Mario Bros. Neither Choice Chamber nor Twitch Plays Pokemon were the first viewer-controlled Twitch game, but Molinari and his team's central mechanic was no longer an obscure idea. "I lost some sleep over it," he says.

But at a GDC event in March, Twitch business developer Brooke Van Dusen asked to see Molinari's game. Unlike Twitch Plays Pokemon, Choice Chamber puts stream members in the position of game designer. Players can do things like build a bridge by typing, pick which of three weapons the player will find in a level, or improve one of their powers. "He played the game, and my 10 fans were on the channel and they played along with him," Molinari says. Impressed, Van Dusen agreed to promote the game's Kickstarter launch. Now, Choice Chamber is becoming the first game to receive funding from Twitch. Five days before the end of the campaign, Twitch is matching the roughly $15,000 that the game has raised so far, taking it past the finish line of $30,000.

It's another step forward for the company, which has spent the past few years turning a simple video service into a platform that can launch careers in streaming or build hype for games like Titanfall — as of today, you can even buy games through it. The "Twitch Plays" phenomenon proved that people could actively use it to play games, not just watch them, and Choice Chamber's timing may have proved serendipitous. That said, while Molinari is confident the game would have reached its goal by the April 20th deadline, it's not clear how much financial support he'd have gotten without intervention from Twitch, and the game is only maybe "5 percent done." In addition to working around 20 seconds of lag, he has to figure out how to make the game as much fun in a stream with 10,000 people as one with 10 (there's also an AI-controlled single-player mode.)

When things go well, viewers seem to like acting as "torture artists," he says. "They want to keep you alive as long as possible, while putting you through as much pain [as possible] without killing you. Whenever the chance to give you more lives comes up, they'll always give you the maximum number of lives. They'll also give you a really crazy challenge, because really, they're there to be entertained." A good player can survive, but they might do so with the worst weapon and the weakest power-ups.

To Molinari, there's no question that people want to play games on Twitch. For now, though, nobody really knows how to make them. How do you give people a feeling of control, for example, without letting the game devolve into unplayability? "There's not too many to compare from, which is why it's so difficult to design right now, and why it's so exciting, because nothing's been done before," he says. But that, he thinks, won't last long. "There's probably going to be a 'Twitch Plays' game jam at some point. I'm sure that's bound to happen, where everyone's going to try their hand at weird ways of having the chat interact with the game."

Michael Molinari is participating in a Reddit AMA this morning.