Gamers dreaming of becoming the next Rakim, 2Pac, or Jay-Z can perfect their flow as industry leader Def Jam and music-game veteran Konami team up to help aspiring emcees in Def Jam Rapstar. On the surface, the game functions as something of a hip-hop Karaoke Revolution, with players flexing their cadence and rhythm to more than 40 hit tracks from hip-hop artists like Notorious B.I.G., Kanye West, Lil' Wayne, and Young Jeezy. But in addition to measuring pitch and timing, Def Jam Rapstar also features new proprietary technology that judges lyrical accuracy. The "Battle" mode isn't designed to match the braggadocio of real head-to-head emcee battles, but it does pit two gamers against each other in a contest to earn high scores, while the "Duet" mode lets a duo rap and sing together on selected tracks to achieve top scores. "Freestyle" mode is where Def Jam Rapstar differs the most from its pop forebears, as amateur lyricists can spit their own freestyles (or writtens) over popular beats from well-known producers.