When Kendrick Lamar said, "Critics want to mention that they miss when hip-hop was rappin’/ Motherf---er, if you did, then Killer Mike'd be platinum," on "Hood Politics," hip-hop heads nodded their heads with immediate agreement. People know what's up when it comes to Killer Mike's skills. The rapper hits the big 4-0 today (April 20).

Last decade, most people immediately associated Killer Mike with OutKast. He made his bars count on "The Whole World" and Stankonia's "Snappin' & Trappin'." However, Andre 3000 didn't want to tour anymore and OutKast went on hiatus. Killer Mike, then too dependent on the seminal duo, was forced to spend a decade as an underground act.

That's not a bad life, though. Mike's booming on-mic presence and distinctive drawl made him an easily recognizable voice. Those characteristics pushed his intellectual lyrics beyond proselytizing, and made him a genuinely likable presence.

Killer Mike already had a solid solo catalog when an act of kismet happened. He linked up with producer and fellow rapper El-P thanks, in part, to Williams Street Records. El-P (who was making a comeback of his own; 2012's excellent Cancer 4 Cure was his first solo album since 2007) produced the entirety of 2012's R.A.P. Music, Killer Mike's best project. The two decided to form the group Run the Jewels and have released two self-titled albums in two years. The first was epic bully rap, and the second was genius in its rabble rousing and political voice. RTJ 2 was easily 2014's best rap album.

So Killer Mike has reached a new peak at an age where many rappers are in their career down slope. This doesn't mean he's comfortable. Mike has used his newfound reach for activism, most notably when he gave an emotional speech during a St. Louis show following the Michael Brown grand jury verdict. He expressed his sentiments about the young man's death and what it means for black youth everywhere. It's one of the moments where you're proud he's one of hip-hop's good guys.

Watch Run the Jewels' "Lie, Cheat, Steal" Video

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