Chris Senn, aka Christian G. Senn, is a video game designer that has worked on a number of Sega Titles during his time at Sega Technical Institute. He worked on The Ooze, Comix Zone, and most notably, Sonic X-treme. His devotion to completing Sonic X-treme in a timely manner is said to have made him so sick that the doctor told him he had 6 months to live and he had to drop out of the project.
Since that time he has gone on to work with other game companies such as Luxoflux, Treyarch, and Bionic Games. Some of the game titles he has worked on include Spider-man 3, Call of Duty: Finest Hour, and two True Crime games (New York City and Streets of L.A.).
Chris Senn also opened a website that showcases plenty of concept art, videos, and other stuff related to Sonic X-treme. This website is known as Sonic Xtreme Compendium, or just SXC. He is active in the forums under the username kurisu.