Zombies and Zombettes, gather ye round. It’s that ghoulish time of year when a guitarist’s thoughts turn to such devilish delights as the tritone, the minor third and – gasp! – even the dreaded flat second! The horror! These demonic musical intervals can create an unsettling feeling in the listener, scare off household pets, open a gate to the land of the undead, and maybe even make a few shirtless dudes crowdsurf.