What does it take for rap music to shock in 2011? The answer was at Friday night's Odd Future show in the First Unitarian Church in Philadelphia, and it's not a pretty list.

The adolescent collective's lyrics boasted all their vilest tropes - sacrilegious screeds, anarchist rape fantasies, and faux-Nazi propaganda, to name but a few - and, as in every other East Coast urban center they visited last week, there was a sold-out crowd there to shout along to every word.

Indeed, the group known as Odd Future Wolf Gang Kill Them All has managed to bring moral outcry about hip-hop back into fashion. Led by the good rapper, great producer, and superb showman Tyler Okonma (alias Tyler, the Creator) - recently turned 20, and nearly the oldest of the seven onstage - it has been denounced by publications such as Slate, fellow musicians Tegan and Sarah, and the Gay & Lesbian Alliance Against Defamation.

Yet for every attack, there has been an accolade: Kanye West has called the group brilliant; Billboard has called it the future of the record industry; and Beyoncé has called at least one of its members to collaborate. Even in Internet years, that is an incredible resumé for a group that was underground just three months ago.

Okonma was in tatters by this final date of the tour, leaning heavily on his charisma and comrades - most notably Hodgy Beats, who ably backed him up on incendiary takes of favorites like "French!" and "Sandwitches." But Okonma screamed his rhymes and surfed the pulsing crowd with all that he had left. By the end of the first song, the asthmatic rapper was gasping for breath; by the end of the set, his voice was raspier than Miles Davis'.

Unfortunately, Okonma seems to have forgotten that this relentless energy is why he has fans in the first place. It was his and Hodgy Beats' adrenalized (and self-censored) performance on Late Night With Jimmy Fallon in February that made Odd Future stars overnight, while his lyrics have since earned him little credit but plenty of critics.

Okonma apologized for his deteriorating voice throughout the night, but that's the last thing he should be sorry about.