Wiz Khalifa at Austin's Club De Ville at Mountain Dew's Greeln Label Sound's SXSW showcase. (Photo: Jessica Lehrman)

In a week filled with surprise guests, the unannounced lineup at Mountain Dew's Green Label Sound showcase Friday night at Club De Ville was arguably just as exciting as its confirmed acts. Rapper Wiz Khalifa and dance-funk singer Penguin Prison joined a roster that already included dance acts like RAC and Starslinger as well as hip-hoppers Mac Miller and Three Six Mafia's Juicy J.

Khalifa was on hand to perform with Juicy J, who recently signed with Khalifa's Taylor Gang imprint on Atlantic Records, as well as to support fellow Pittsburgh native Mac Miller. Fellow Taylor Gang rappers Chevy Woods and Lola Monroe also took stage during the surprise set.

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Penguin Prison popped up halfway through DJ duo RAC's set to debut a new single, "Hollywood," set for release in April exclusively via Green Label Sound. As he introduced his new RAC single, the band's Chris Glover asked the crowd, "Who out here lives in Los Angeles? Who here doesn't live in Los Angeles and hates it? Well, this song is about a girl who moved to L.A. and how it changed her life."

The unannounced lineup at Mountain Dew's Green Label Sound showcase was perhaps just as exciting as confirmed acts as Rapper Wiz Khalifa and Penguin Prison joined RAC, Starslinger, Mac Miller and Three Six Mafia's Juicy J. (Photo: Jessica Lehrman)

In other Dew news, the PepsiCo brand is set to back Miller's Macadelic Tour when it kicks off March 27 at Norfolk State University in Virginia. Green Label Sound labelmates Cool Kids will support. The Macadelic gigs come on the heels of Dew's fall 2011 support of Holy Ghost's first headlining tour. As the band told Billboard.biz in October, budget issues would have made it cost prohibitive for the band to tour with opening acts without outside support. "Everyone thinks going on tour is awesome, all the girls and whatever and awesome shows," Holy Ghost's Alex Frankel said at the time. "But the reality of touring for a band at our level now is without a major label or tour support, there's a tremendous of logistical support needed. It's awesome when someone comes in and says, 'We're gonna help you.'"

How Mountain Dew Booked Lil Wayne for SXSW, DeWeezy Campaign

Friday's showcase came just one night after Mountain Dew announced that Lil Wayne would be its latest artist partner via a new endorsement-meets-philanthropic program called "DEWeezy." Performing at the Young Money/Cash Money Records showcase Thursday night, Lil Wayne even filmed a live commercial for the upcoming campaign, which will include TV, digital and print as well as the building a skate park in his hometown of New Orleans. Young Money Nicki Minaj is set to announce a partnership with at least one other Pepsi brand in the coming weeks, Billboard has learned.

Amid the hip-hop heads and dance fans, brand execs like Mountain Dew's brand manager Hudson Sullivan and Converse chief marketing officer Geoff Cottrill, who made the rounds after closing up shop at the Converse-sponsored Fader Fort for the night.

Wiz khalifa with Lola Monroe (Photo: Jessica Lehrman)