Sometimes the most unlikely combination of artists yields the best splits. Such is the case with Feistodon, the new split between indie pop singer/songwriter Feist and metal band Mastodon released for Record Store Day 2012. Both acts are critical darlings in their respective groups, but collaboration between the two still seems a little off the wall.

At least, until one plays the resulting seven-inch. Feistodon follows a simple split play: Each act covers a song from the other's respective 2011 album. Mastodon goes first with "A Commotion," from Metals. What's so weird and yet so very awesome about Mastodon's take on the track is that so much of the song translates fairly well. The band takes the simple guitar progression that provides the song's through line, adds a little bit of chugging to performance and from there on out the song just gets more and more metal. By the time the band hits the half-time break on the chorus, "A Commotion" has already become the best song to come out of RSD this year.

Mastodon's cover is arguably the winner here, if only because it dresses up such a pretty little indie song in sludge metal trappings. But Feist does the same thing in reverse with "Black Tongue," from The Hunter. "Black Tongue" Feist's solo material has always had a quiet, subtle touch to it, but here, she harkens back to her noisier days with Broken Social Scene. Feist retains the central riff to Mastodon's song, but the presence of such snarling electric guitar over what is otherwise a sparsely arranged cover gives the song a menacing, haunting feel.