In January 2009, M. Shadows confirmed that the band was writing the follow-up to their self-titled fourth album within the upcoming months. They also played at Rock on the Range, from May 16–17, 2009. On April 16, they performed a version of Guns N' Roses' "It's So Easy" onstage with Slash, at the Nokia Theater in Los Angeles. On December 28, 2009, the band's drummer James "The Rev" Sullivan was found dead at his home at the age of 28. Autopsy results were inconclusive, but on June 9, 2010, the cause of death was revealed to have been an "acute polydrug intoxication due to combined effects of Oxycodone, Oxymorphone, Diazepam/Nordiazepam and ethanol". In a statement by the band, they expressed their grief over the death of The Rev and later posted a message from Sullivan's family which expressed their gratitude to his fans for their support. The band members admitted in a number of interviews that they considered disbanding at this point in time. However, on February 17, 2010, Avenged Sevenfold stated that they had entered the studio, along with now-former Dream Theater drummer Mike Portnoy, to drum for the album, in place of The Rev.