Razgriz

Absolutely love the comic, haven't seen the show or the movies. Not yet, anyway. I'm waiting for the U.S. serialization of the comic to end before I go any further into the other media. It's actually the only comic I read regularly, even more so than keeping abreast of American comics.

Pentatonic scales help a lot, yeah. Also, if you're playing over a rhythm (as you are here) it sometimes helps if you listen to the parts you play well, then just repeat them. Keep in mind that holding one note significantly longer than you normally would can sometimes trigger new motifs. Finally, borrow pieces from the vocals and basslines. It can reinforce the melody and buy you some time to come up with a few new patterns.

You can also try applying a very short delay to the sample for the multiple-drummers-at-once effect. I've found this gives a cleaner effect than plain old reverb, but it's a personal preference. I usually run it through reverb afterwards, anyway.