Metalcore Downpicking Exercise

This is a nice exercise in drop-d tuning I'm using to train downpicking and pedal riffs. I've divided the exercise in different speed I'm still working on getting the final speed tight. As you might have notice, I've switched to alternate picking on the last part of the riff because my forearm was on fire! Sixteenth notes at 110 BPM equals eight notes at 220 BPM, which is roughly the speed of Master of Puppets.