With a cover photograph of 40-year-old Biz Markie sitting naked in an Indian headdress, Weekend Warrior makes clear that Biz is the Peter Pan of rap. He is forever young, or at least he serves as guardian to hip-hop’s fountain of youth. With Biz every listener is given the opportunity to revert back to his or her teenage self, when hip-hop was a new and exciting discovery, a culture that demanded only that we be ourselves. Weekend Warrior reaffirms Biz’s old-school values while also preventing him from becoming a novelty act. Ironically, his experiments in new styles are the songs that sound the most dated. While you have to respect him for trying new things, the syrupy “Like a Dream,” the Timbaland-aping “Ei Ya,” and the bizarre dancehall collaboration “Let Me See U Bounce” don’t quite fit him — like a sneakerhead trying to rock patent-leather dress shoes. The oldest, simplest-sounded songs are the ones that still seem fresh — like an old pair of Adidas. “Tear S**t Up,” “Chinese Food” and “Party to the Break-A-Day” don’t come off like relics, but reminders of the timelessness of a certain hip-hop formula — breaks, loops, and Biz’s inimitably lumbering-yet-funky flow.