My friend has a tapping riff at frets 8, 11, and 15 (on high E string). he wants me to find him a song that he can play it with, but i haven't had any luck. Anyone got any ideas? if the riff needs to changed, please tell me!

peace out!
make it in E, so shove it up 4 frets
then make a few slayer/metallica style riffs for the bottom. lots of palm muted open bottom E notes with a few power chords like G5 and A5 sprinkled around