Saddle up, suds lovers: One of the most interesting beer festivals in Colorado returns to Denver on March 16—and it’s shaping up to be a doozy. Now in its sixth year, the Collaboration Beer Festival, headed up by the Colorado Brewers Guild, is set to pour more than 100 collab brews created by teams from 200-plus breweries from across the state, the nation, and even overseas. “Collaboration Fest is essentially a huge family reunion for brewers and craft beer drinkers alike,” said Steve Kurowski of the Colorado Brewers Guild.

Brewers use the teamwork-oriented festival as more than just a chance to bond with their compatriots in the industry, however. The resulting one-off brews also present a chance to push boundaries and flex creative muscle; attendees at this year’s festival can expect to sip on everything from milkshake IPAs to mushroom-infused lagers. Here are six brews not to miss at this year’s fest.

Beer: Grafted In Paradise
Brewed By: Purpose Brewing and Cellars and Paradox Beer Company

Peter Bouckaert, co-owner of Purpose Brewing in Fort Collins (and former brewmaster at New Belgium), literally wrote the book on the relationship between wood and beer. So it doesn’t come as much of a surprise that Purpose is partnering up with Divide’s Paradox Beer Co. to create a beer centered around Bouckaert’s research on alternative wood aging and Paradox’s research on microbes. Expect their complex beer—listed as a modern farmhouse ale—to be slightly tart with delicate flavors of cinnamon, amaretto, and orange imparted during the aging process.

Beer: Where I Leave
Brewed By: New Belgium Brewing Company and Trve Brewing Company

If you’re a fan of sour-style brews, New Belgium and Trve’s collaboration is a must-try. The breweries worked together on two versions: Trve’s version, Where I Leave, is a blend of some of New Belgium’s foeder-aged sours and some of Trve’s barrel-aged sours. New Belgium’s take on the blended collaboration, Where I Live (both names stemming from songs by Belgian black metal band Oathbreaker), will be released sometime in November.

Beer: Meet the New Boss
Brewed By: New Image Brewing and More Brewing Co.

Stout Month may be over, but that didn’t stop New Image Brewing Co. from creating some dark and roasty goodness to pour at this year’s Collaboration Fest. The Arvada-based brewery, and More Brewing Co.—a Chicago-based brewery known for its New England IPAs, sour-style brews, and stouts—created an extremely high-gravity dessert stout that is set to weigh in around 12 percent ABV. The beer is a classic take on a South American mocha coffee and features adjunct flavors like vanilla, coffee, chocolate, and cinnamon. When the steady stream of hazy IPAs gets tiresome, head over to the New Image booth and mix things up with a pour of this hefty stout.

Beer: Primordia
Brewed By: Crooked Stave Artisan Beer Project, Mockery Brewing, Great Divide Brewing Company, Black Shirt Brewing Co., Epic Brewing Company, Our Mutual Friend Brewing Company, and 14er Brewing Company

From the great minds behind seven RiNo breweries comes Primordia—a mushroom Schwarzbier (dark lager) named after the last stage of the mushroom’s development as a fruiting body. Using a traditional German Schwarzbier base, this unique beer incorporates two additions of mushrooms (oyster and shiitake) totaling 26 pounds. The mushrooms were sourced from the GrowHaus, a non-profit indoor farm and market in north Denver.

Beer: Trade Secrets
Brewed By: WeldWerks Brewing Co. and Cerebral Brewing

Two of the state’s most celebrated breweries, both known for creating stand-out IPAs, are teaming up to brew a New England-style Double IPA. Brewed with a combination of Nelson Sauvin, Sabro, and Citra hops, this smooth-drinking, hoppy brew will surely garner a line throughout the event, so mark this collaboration as one to seek out early on.

Beer: SMASH in Space
Brewed By: Sanitas Brewing Co. and BJ’s Restaurants and Brewhouse

Space yeast is thing, and you can try it for yourself in Sanitas Brewing Co.’s SMASH (which stands for single malt and single hop) collaboration with BJ’s Restaurants. Using yeast that has left the earth’s atmosphere as part of a research program at Red Rocks Community College, the beer highlights as many “out of this world” ingredients and brewing techniques as the collaborating brewers could concoct—like incorporating Galaxy hops and brewing at zero gravity. “We went with a SMASH so that we could do as little to the beer as possible to let the yeast shine through,” said Michael Memsic, co-owner of Boulder’s Sanitas Brewing Co.

If you go: Collaboration Fest takes place on Saturday, March 16 from 2 to 6 p.m. at the Hyatt Regency in downtown Denver. You can purchase tickets here.