 On July 17 , 2012 , a tweet from the Twitter account for Megadeth 's mascot Vic Rattlehead implied that frontman Dave Mustaine had begun writing lyrics for a follow @-@ up album to 2011 's Thirteen . In an interview with NME , Mustaine confirmed that the band had been working on new material , commenting : " Some of it 's a little darker , some of it 's a little faster . " 
