When WCW wrestler, Sting, walked to the ring, he had a live version of "Seek & Destroy" playing over the PA. When the soundtrack of WCW was released, Metallica contributed that track, a live performance from Woodstock '99, to the album. 

"These days entertainment is all about synergy and cross-merchandising baby, from the "free" toys at the burger joint to the pay-per-view rights, soundtrack CD, T-shirt sales, and cereal endorsements, et al. The wrestling establishment has become increasingly savvy at such activity, and this CD would seem to be the culmination of this marketing ethos. WCW Mayhem brings together new and exclusive tracks from some of the hottest hip-hop (Cypress Hill, Lyrical Giants), metal (Metallica, Slayer), and hip-hop-metal acts (Kid Rock, ICP) as well as the entrance themes for the hottest WCW superstars (from Goldberg to the Nitro Girls). Does it deliver? Hell yeah; this disc is as rowdy and entertaining, boastful and testosterone-fueled as the sport that it celebrates." - Mike McGonigal