"Mr. Scarface," from Mr. Scarface Is Back (1991)
It's kind of hard to believe due to the content of the song, but "Mr. Scarface"—which features a sample of Al Pacino's character in the movie Scarface—was actually a huge single for 'Face, peaking at No. 8 on the Hot Rap Singles chart. But after hearing it, it's not hard to hear why Mr. Scarface Is Back is one of the most revered gangsta rap albums of all-time.
"Tha King," from Urban Legend (2004)
A lot of thought went into this entry, because when Tip stopped by the VIBE offices a couple years ago to preview Paper Trail, the intro song "56 Bars" and the second song "I'm Illy" were originally combined into one long song, making it one of the most impressive displays of lyricism we'd ever heard from T.I. He split them up, though, so we gotta give the nod to "Tha King" here as the King's best intro of all-time. He earned his crown on this one.