Kyle Richard Gass (born June 14, 1960) is an American actor and a member of the band Tenacious D (along with Jack Black) and Trainwreck. In Tenacious D, Gass plays lead guitar and sings backup vocals, and also plays the role of Black's comic foil in most of their comedy routines. He is often referred to as KG, My Brother Kyle (by Jack Black) or Kage, although he is sometimes given the nicknames Rage and Rage-Kage, in-jokes about his very calm personality. He is also known as "The Other Half of Tenacious D". He is Samuel Wyatt Black's godfather.