Sia and Kanye West teaming up is big news. Sia is one of the most popular pop stars of the last couple years (and has written plenty of smash hits for other stars in the last decade) and Kanye is...well, he's Kanye. Plus, who can forget when the two paired up for Kanye's big performance at the SNL 40th anniversary special. Anyways, Yeezy co-wrote and co-produced Sia's latest single, "Reaper," off her upcoming album, This Is Acting. And it's more of that vibey artpop that she's been peddling since "Chandelier" took over the world a while back.