Supergroups sound good on paper, but they don't always work out. The Fugees, arguably the greatest hip-hop supergroup in history, could only keep it together for one album. The four-headed monster known as Slaughterhouse is the next and perhaps the best evolution of the hip-hop supergroup. Their second single, "Onslaught 2," is a manual for aspiring rappers with punchlines that will send you searching through that old rhyme dictionary. Pay attention.

Who goes harder than the slaughter?