Controversial (maybe that should be “controversial”) experimental-rap outfit Death Grips has been defined as much by its image/publicity stunts—leaking its own record in order to piss off its label, putting a penis on an album cover, not showing up for Lollapalooza as some sort of statement—as its music (which is nonetheless occasionally great). Last night, the band continued its surprising, confounding schedule with the free-download release of Niggas On The Moon, the first half of a planned double album called The Powers That B. The band’s Facebook page says that this half-album features Björk on all eight tracks, but fans of the Icelandic pixie shouldn’t go in expecting big choruses—or even a terribly recognizable presence. Her voice seems to be sampled (though it may have been recorded specifically for this project), and it mostly provides color to the background: On “Black Quarterback” and “Big Dipper,” it’s just a wail; almost everywhere else it’s not evident at all. Could this selling point be just another not-that-threatening middle finger/publicity stunt? Yes, yes it could. In any case, the album is available for free download via that Facebook link above, or you can listen to it below via Soundcloud. Death Grips will play the Pitchfork Music Festival in Chicago next month, before joining the Soundgarden/Nine Inch Nails giant-venue tour this summer, where it will attempt to prove those giant bands still have some danger left in ’em, at least by proxy.