"Warm" isn't a word generally applied to Killer Mike or El-P. After all, Run the Jewels — a new album synergizing the veteran rappers — hinges on two MCs who pride themselves on thinking five steps ahead of their opponents and writing punchlines that cut with a butcher's precision. On past albums, Mike (a.k.a. Michael Render) has boasted about robbing tourists outside a strip club in his hometown of Atlanta, and Brooklyn's El (a.k.a. Jaime Meline) noted, "I loved the part where you cried / I like nothing else." But a moment of profound affection unexpectedly emerges on Jewels' "Banana Clipper." "Producer gave me a beat / Said it's the beat of the year," Mike raps. "I said, 'El-P didn't do it / So get the fuck out of here.'" That show of camaraderie makes a whole lot of sense considering each recently has played a fundamental role in energizing the other's reputation. In 2012, El-P wrote and produced his own Cancer 4 Cure (which had Mike in a feature spot) while Killer Mike issued R.A.P. Music, a record whose craggy, hypnotic tunes were masterminded by El. (Of course, El showed up for a vocal cameo, too.) Both Cancer and R.A.P. were among last year's most on-point hip-hop albums, so it's a very good thing that the pair continues the course of its Batman-meets-Superman routine.