Gene Simmons is getting ready to rock out for one last time. The KISS musician spoke with ET's Kevin Frazier in Las Vegas during a three-part interview at Simmons' home and the KISS World Museum at the Rio Hotel and Casino, where he dished on the band's world tour, which will mark their final time touring as a group — and how at 72 years old, he still has the stamina to do it all.«We start playing the outdoor stadiums of South America, literally within two weeks, and continue on to Europe and Australia and eventually North America, Japan, all that stuff.