Mr. Butcher is not the only author to come out of the Amber community: by some estimates, a dozen or more of the hundreds of former players have gone on to become published authors. Playing Amber then was like attending a writers’ colony, but without the brie and posturing.

“Some of those people wrote so well, I’d be terrified of gaming with them,” C. E. Murphy, an author of fantasy novels who lives in Ireland, said by e-mail. “But it made me try harder when I did encounter them. I wanted to be worthy, essentially, so I stretched my talent to try to match what I perceived of as superior skills.”

The need for speed helped break down writerly inhibitions, Ms. Murphy recalled. “Because it was real-time, happening as fast as we could type, there was no going away for a week to worry and fuss over whether your story was good enough to stand up to another critique partner’s abilities. We did our absolute best in the spur of the moment, and I think that kind of fresh, fast response is incredibly helpful to many writers.”

It was “an insanely positive writing environment,” she said, and added: “If we had a rule of storytelling on Amber, it was ‘no’ kills the game.”

Cam Banks played Ambermush as a teenager in New Zealand and later moved to the United States, where he is now creative director for Margaret Weis Productions, a small, award-winning maker of role-playing games, the face-to-face kind with the many-sided dice. He published his first novel in 2007 and allowed that Amber could, in fact, be bruising to the ego, even in the details of creating the virtual rooms that were settings for the game.

“If you don’t write a good scene, if you don’t paint the right picture, people don’t come into your room,” he said. “People would just mock you openly.” But, he added, that kind of treatment “would lead you to trying harder or getting better.”

Angela Beegle, a writer of romance and fantasy fiction, said writing for the Ambermush community had helped her to develop her characters. “My first male character was a cardboard cutout,” she explained. “He swore, he belched and he leered. I’ve gotten much better since then.”