Well, that was awesome.
After getting off to a kind of flat start, Mastodon found their groove in the third song, which is where they hooked me. These guys are nuts—their drummer, particularly; dude was throwing all sorts of crazy jazz accents in there. Plus, they ended with a Melvins cover, which put them even higher in my book.
As for the openers, I arrived too late for Cult of Luna, but just in time for the start of Death by Stereo's set. Awful metalcore band, with the only redeeming moment being when the singer introed a song by yelling at the audience, "I want everyone to flip me off right now! I want to feel your anger! I want to feel your rage ARUGHGGHHHGUUGGHGHH!" Ridiculous.