 Guitar Hero World Tour , previously named Guitar Hero IV , is the fourth full game in the series and was released on October 26 , 2008 for PlayStation 2 , PlayStation 3 , Xbox 360 , and Wii . Analysts had expected that future Guitar Hero games in 2008 would include additional instrument <unk> to compete against Rock Band ; Guitar Hero World Tour was confirmed as in development following the announcement of the merger between Activision and <unk> Games in December 2007 . Activision 's CEO Bobby Kotick announced on April 21 , 2008 that Guitar Hero World Tour will branch out into other instruments including vocals . Guitar Hero World Tour includes drums and vocals , and can be bought packaged with a new drum set controller , a microphone , and the standard guitar controller . A larger number of real @-@ world musicians appear as playable characters , including Jimi Hendrix , Billy <unk> , Hayley Williams , <unk> <unk> , Ted <unk> , Travis Barker , Sting , and Ozzy Osbourne . Guitar Hero World Tour also features custom song creation that can be shared with others . 
