Fast-food chain White Castle partnered with iconic hip-hop group Wu-Tang Clan to promote the Impossible Slider ahead of the chain’s expansion of the vegan-friendly burger to locations nationwide. White Castle shared a promotional video on Instagram, wherein Wu-Tang member and longtime vegan RZA directed followers to a hotline set up to promote the Impossible Slider. “Peace. My name is RZA9000, formerly known as the RZA. I have uploaded my consciousness into a supreme data system and now I possess the knowledge infinite,” the disembodied voice of RZA says in the video. “Together with the Wu-Tang Clan, we will slide through space, seek wisdom, and expand the parameters of the mind. If you are an Earthling and you need answers, call 1-833-4-SLIDER.” The phone number connects to a recorded message, wherein RZA urges callers to leave a “question about existence” that may be used as part of the campaign, ending the recording with a cryptic statement. “All will be revealed. Wu-Tang in space, eating vegan Impossible Sliders—October 1.” Wu-Tang members Ghostface Killah and GZA have posted various teasers related to the campaign on their social media networks. In April, White Castle trialed the Impossible Slider (which can be ordered vegan by omitting cheese) at 140 select locations and reported that some outposts sold upwards of 300 plant-based burgers per day. Last week, White Castle announced the expansion of the vegan-friendly burger to all of its 377 locations nationwide, a move supported by Kal Penn—the “aspiring vegan” actor who famously portrayed “Kumar” in cult-classic film Harold & Kumar Go to White Castle, who is also a collaborator in the Wu-Tang campaign.