A Cover Version of a song is a song that is recorded by a different artist than the original. Cover versions are mostly used in Guitar Hero because of an artist not allowing the use of the original Master Track or otherwise not having the master track available. Cover versions are shown with the phrase "as made famous by," for example; "Heart-Shaped Box as made famous by Nirvana." Every Guitar Hero game since Guitar Hero World Tour does not contain any covers, although the downloadable tracks "Gimme All Your Lovin" and "Black Betty" are covers.