Earlier this month, we heard UK psych-thump pioneers Burial and Massive Attack collaborate on a new song called "4 Walls" and now here's that single's B-side, a Burial rework of Massive Attack's "Paradise Circus." It's pretty heavy. [videoembed size="full_width" alignment="center"][/videoembed] The 12? is out now on Inhale Gold/The Vinyl Factory, and it’s limited to 1000 copies.