Former boxing king Mike Tyson showed up to knockout a promotion and sign autographs for RockLive’s new iPhone/iPad game, "Mike Tyson Main Event" at South by Southwest (SXSW) Interactive Festival on Sunday, March 13. The champ appeared approximately 45 minutes late, and forced a handful of models sporting henna ink versions of the boxing legend's unique tribal tattoo on their faces to keep the crowd at ease. RockLive had Tyson meet-and-greet fans and sign autographs for two and half hours inside a large a boxing ring at the Screenburn arcade exhibit. Several celebrities will be appearing in the iPhone game's updates and is rumored to have such personalities as Osama bin Laden and John Lennon and the possibility of adding characters from the film or the upcoming sequel of "The Hangover," scheduled for this summer. Demos of the game were available to play at the show's Screenburn arcade and will be available for sale on the iTunes store.