In November of 2014, 180 part-time witches and wizards descended on a Polish castle for a weekend of live-action role-playing. Dropped into the universe of Harry Potter, they made friends and fought the forces of evil while doing homework for Defense Against the Dark Arts and vying for the House Cup. "By the time the game ended on Saturday night, I had prophesied the resurrection of a dark wizard, fed a faun a lollipop, snuck down a secret passageway in my pajamas to join a secret society, and battled a fellow student to a standstill in a magic duel while trying not to trip on the dress I'd worn for the dance," wrote participant and veteran larper Shoshana Kessock. "And of course, I aced my Magical Artifacts class."

College of Wizardry, as the experience was called, was a carefully produced Nordic larp — a form of role-playing that's heavy on atmosphere and light on hit points and spell damage calculations. Nordic larpers stay in character for days at a time, weaving their own stories into a loose larger plot. And while College of Wizardry definitely wasn't the first Harry Potter larp, it captured public imagination in a way few other projects have. "Larpers have been doing larps set in their favorite fictional universes for years, all over the globe. What made CoW stand out was that it got so much attention," says organizer Claus Raasted, a prolific contributor to the world of Nordic larp.

When the team decided to hold it again, the project appeared everywhere from BuzzFeed to USA Today. Tickets for the upcoming April run, which cost around $350 apiece, sold out in under two minutes. Today, anyone who missed out will get another chance — and potentially a much bigger one. Today, Raasted and the team are launching an Indiegogo campaign, seeking $50,000 for a November 2015 encore show. At $120,000, they'll add another. At $175,000, College of Wizardry will play three times in November.

And if they get $1 million, they buy a castle.