What do you do when the international scavenger hunt you created has already broken seven Guinness Book of World Records, raised unmatched charitable donations, and captured the attention of celebrities and fans all across the world? You take that scavenger hunt on a road trip in a broken down RV, of course!

At least that’s what Supernatural star Misha Collins decided to do with this year’s Greatest International Scavenger Hunt the World Has Ever Seen (GISHWHES). Theannual worldwide weeklong scavenger hunt that brings together thousands of participants from over 100 countries to complete creative, kind and hilarious stunts, all in support of the non-profit organization Random Acts. For its fifth year, Collins is taking GISHWHES mobile in the GISHBUS as it travels across the country before ending up at San Diego Comic-Con later this month. Since Collins helped launch the GISHBUS in Los Angeles, it has made its way across the country, making stops in major cities. Nerdist got Collins on the phone immediately after he met up with the GISHBUS at the Atlanta stop, the first time he reunited with it since the launch.

“The fact that it has made it all the way to Atlanta is a feat of engineering and human ingenuity, because it is a piece of shit 1976 RV that I really wasn’t expecting to make it out of Los Angeles County, let alone all the way across the country,” Collins tells Nerdist with a laugh.

But what is the GISHBUS? “There’s a twofold idea behind the GISHBUS,” Collins says. “One is: we wanted to give our frequent GISHers a VIP experience, so we decked out the interior of this RV and made it available exclusively to people who have obtained a certain tier status with GISHWHES, which basically means they’ve participated in the hunt for a certain number of years. But we additionally gave people access to the GISHBUS at each of the stops if they brought a donation to a local charity in the community where the GISHBUS was stopped. So we found a way to tie in VIP points reward systems with getting people to be charitable as we travel around the country.”

According to Collins, each of the stops has been a huge success in helping to spread the word about GISHWHES, getting GISHers excited about the fifth annual scavenger hunt, as well as raising incredible amounts of charitable donations before the hunt even begins. “People are showing up in droves and the amount of supplies they’re bringing for local charities is astounding,” Collins says. “There have been piles bigger than the actual GISHBUS accumulated. That’s so awesome, to see this amount of contributions. It almost feels like people are looking for an excuse to do something good, and it’s nice to help be able to facilitate that.”

But for something so important in helping to kick of GISHWHES, why did Collins decide to make the GISHBUS out of something even he calls “a piece of shit?” (Hey, those were his words!)

“There was a lot of sitting around and discussing various ideas and laughing,” Collins says. “And I’m going to reveal a secret that I normally don’t talk about—we have an official GISHWHES complaints receptacle on the bus. There’s a form you can fill out with any complaints and you put this form into a slot and immediately you hear the sound of an automatic shredder turning on and it shreds your complaint.” He laughs. “I thought that was a work of customer service genius.”

Other elements of the GISHBUS that immediately crack Collins up: “The upholstery in the RV is made of maxi pads. The curtains in the VIP executive lounge are made from socks. The table is made from a bunch of Etch A Sketches wedged together. And then there is a V-VIP room where only the most exclusive, highest tier status GISHers can actually go. And in that room… I won’t tell you all the details, but there is a very, very special film paying homage to William Shatner in a phase of his life when he’s clearly smoking a lot of pot. So it’s really got something for everyone. There’s live-streaming functionality, the bathroom has a black light in it, and in order to enter the bus you have to sign a non-defecation agreement, which means you promise you won’t shit on the bus. It’s truly a VIP experience.”

While Collins hasn’t been riding the GISHBUS for its entire route, he’s been there for the GISHBUS team for moral support … which they’ve needed plenty of.

“The only challenge has been that the GISHBUS has spent more time in repair shops than it has actually on the road,” Collins says. “It has had virtually every hose, wire, radiator, distributor, gasket, fuel pumps, fuel tanks, everything has been replaced at one point or another. The folks that have been driving the bus, I’ve had to console them. At one point one of them was crying in the automotive section of Walmart while traveling across the country and they were trying to find a silver lining in the whole experience. I said, ‘Well, you have made friends with lots of mechanics!’ There’s always a glass-half-full way of looking at things.”

For fans looking to get involved with GISHWHES this year, prepare to take on a list of items that are even more out-of-this-world than previous years’ … literally.

“We’re always looking for new, bizarre challenges that are on that cusp of possible and the impossible,” Collins says. “We have a couple of challenges that are space-related that we’re kicking around right now, like space travel, NASA, SpaceX. Those get me excited. And we have a complete treasure trove of items that we have been assembling for the past 12 months that I think are going to make this year’s hunt better than ever.”

If space travel sounds like an impossible task for your average GISHer, Collins urges all participants to use their imagination. The more creative the submissions, the better. But hey, if someone can actually go into space, that’s cool too! He wouldn’t put something on the list that literally no one could achieve … right?

Well, not so much. “There’s always some things we knock off the list because we know nobody is going to be able to get that done. I say that, but then again we do every year put math problems on the list that have never been solved by any mathematician in the world,” Collins says. “So maybe we have set the bar kind of high. But thus far, people have come up with some very creative answers, none of which have actually been able to prove the theorems, but still. We’re working on that. It would be awesome to actually achieve the previously thought impossible. And we have broken seven Guinness World Records to date so that feels big all on its own.”

As for GISHWHES celebrity fans, Collins reveals that Jason Manns, Ruth Connell, Justin Guarini, Briana Buckmaster, Richard Speight, Kathryn Newton, Matt Cohen, Osric Chau, Kim Rhodes, and Rob Benedict have already gotten involved with this year’s hunt, either by contributing an item or joining the hunt themselves. But what about GISHWHES’ biggest fan, William Shatner?

“Oh, of course. He’s a staple at this point,” Collins says. “Honestly, I think he would be really incensed if we didn’t include him. To be perfectly honest, I think William Shatner pins a lot of his self worth on the extent of which he’s included in GISHWHES. It would be psychological warfare if we didn’t include him.”

Collins pauses, and then adds, “Which, now that I’m saying it, maybe then we shouldn’t … I don’t know. That might be just the thing! Maybe we should try to piss him off with the hunt this year. This has been a good brainstorming session, thank you!”

Images: GISHWHES

This year’s GISHWHES will take place July 31-August 6, and registration is currently open at www.gishwhes.com. The winning team of 15 members will go on a once-in-a-lifetime, all-expenses-paid trip to Iceland with Collins.