Promoters in Kansas City’s East Side rap scene have been bringing big-name artists to town for years, right under the noses of us mainstream types. They usher these artists through the back door; festoon them with cash, champagne and women; hand them a mic and a crowd; let them rap; and escort them out under cover of darkness. This Halloween marks the arrival of Atlanta hotshot Lil Scrappy, who is no longer “living in the projects, broke with no lights on” (as his 2007 hit indicated), thanks to production help from Lil John and 50 Cent and plenty of big-label money. You, too, can cash in at Scrappy’s show by wearing a costume worthy of the $500 contest prize. (For women who need ideas: Just pick up a hip-hop party flier.) Joining in on the crunk mischief are locals Rich the Factor, Black Walt, Chain Gang Parolees, D-Locc da Chop, Cash Image, Block Life, Greedy and others. Admission is one Andrew Jackson.