For the opening riff, I decided to break out with a classic Lamb Of God-style thrash riff which occurs in two parts. Measures one through eight consisting of mostly low D chugging (with higher single notes on the A string to break up the monotony), along with two different transitions: one being a Wrath-style double 12th fret bend, the second taking a more chordal approach.
When we reach measure 9, we DO continue the low note with higher "chops" routine, except this time with "octave chords" to emphasize the voicings a little more.
Measures 13-19 are pretty self-explainatory - just a doomy chord section to set us up for our verse. Speaking of which, let's do it!
The picking patterns are a little non-conventional for the purpose of achieving the heaviest pick attack while still remaining as ergonomic as possible.