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There’s a new kind of hybrid game doing the rounds that marries the large scale politicking of live-action roleplaying (LARPs) with the focused, often crunchy mechanics of an economic game. It’s played with dozens, even hundreds of players, it takes a whole day, and it has a clumsy sobriquet that perfectly encapsulates its grand ambition: the “megagame.”

Megagames have no strict definition, but here’s an outline of the (pretty typical) first one that I tried two years ago. Strange alien forces mass near the earth, alarming the world’s governments. Multiple teams of three-to-six players represent various nations, and teams take on roles like diplomats or military leaders. Each team plays its own straightforward game of economics to balance a country’s budget, fund the military, and direct scientific research.

These aspects of the game are all managed in “private play areas” depicting each country, but players also meet in more public areas to coordinate international strategic planning or to discuss diplomatic goals. They pore over a map of the world showing the movements of their armies and air forces. They huddle around a table that represents the UN. They forge alliances, compete to seize alien technology, and perform acts of espionage.

Occasionally a referee steps in to clarify a ruling or to announce a new event. Alien craft have been sighted on the Moon! Terrorists have kidnapped a head of state! Earthquakes! Perhaps there’s even a message from the aliens—who are played by another team of people kept separate from the action but nevertheless allowed to watch everything as the nations of earth banter and bicker.

This is Watch the Skies, only one kind of megagame, but so far the most popular. It’s enjoying replays and reinterpretations everywhere from Aberdeen to Australia. If your personal preference isn’t for the extraterrestrial, other megagames cover everything from military scenarios to Machiavellian historical intrigue. What they all have in common is a focus on social dynamics, independent referees who guide play and introduce new events, and a sense of scale that puts Diplomacy to shame.

They also share a lineage. UK-based Megagame Makers has been designing and playing these games for decades, long before Watch the Skies found breakout success. A key designer throughout much of this period has been Jim Wallman, and when I speak to him over Skype to ask the secret of a megagame’s success, I discover he has recently returned from a game in Canada and is consulting with the British military on simulating conflict scenarios.

Perhaps surprisingly, Wallman says the key to running a good megagame is “not overdesigning it.” Compiling acres of rules and elaborate systems can be tempting, but the scale and possibility present in megagames means there simply can’t be a rule or system for every event. “You make a framework, but you can’t plan for everything,” says Wallman. “You have to let go.”

Just as important as any ruleset are the referees, who fill roles similar to the GM in a tabletop RPG. They must be adaptable and willing to run with the inevitably unexpected suggestions players will make. “Every game is going to go off the rails,” Wallman says. “And I enjoy that.”

Case in point: the last megagame I played (when our Shut Up & Sit Down team attended an enormous 300-person event in London) saw the pope become an envoy to extraterrestrials and the entire UN get kidnapped.

“You have to trust [your referees],” Wallman says. “That’s how things like this happen.”

On the other side of the world, Jack McNamee is preparing God Emperor, a pseudo-historical game of war and intrigue to entertain the people of Brisbane. Despite all his personal preparation, McNamee agrees that a reliable team of referees (or “control members”) remains vital on game day.

“When I run a [traditional] RPG, I improvise almost everything,” he says, “but when you have 12 control members, you need to set out these strict plans saying, ‘This is how we improvise.’ You need to set communication structures in place so that the improvisation feels real and appropriately affects the whole game.”

God Emperor speaks to the growing diversity found in megagaming, being both thematically and functionally different from Watch the Skies. McNamee describes it as “a worker placement game, where the human beings on your team are your workers.” Three smaller, interlinked games cover war, politics, and espionage. Each turn, the team decides where to send its five players.

“The more people you send to a game, the more effective you’ll be,” McNamee says. “If you send everyone to the War Map, your military will be incredible, but you’ll have no way to stop assassinations from the Espionage game or block harmful laws from the Court.”

And much as Watch the Skies draws its influence from other science fiction games such as the X-COM series, God Emperor has a familiar fantasy flavor. “Melissa Hearn had the original idea of ‘A Megagame of Thrones’ before eventually handing it over to me,” says McNamee. “The intrigue, backstabbing, and politics of Game of Thrones are a natural fit for a megagame, and [the original] Megagame Makers are now doing a similar thing with Everybody Dies.”

(Though scheduled for November, Everybody Dies is already full, a not uncommon situation in megagaming. Wallman tells me that games are increasingly booked up months in advance.)

Want to try a megagame yourself? Even if you can’t find space in a megagame near you, nothing’s stopping you from creating one yourself. Wallman and his colleagues could have been strict and stingy about how and where they have shared their creations, but instead they have happily provided all sorts of advice, materials, and information to dozens of new megagame groups around the world. The main objective is to get more people playing.

“When you start, you’re going to worry about finding a venue, pieces, art, fifty players, and so on,” says McNamee. “This is secretly easy: the solution is just to ask for help. I got started in this forum thread, and amazing people offered up a great venue, graphic design, art, and everything for very cheap or free.”

The megagame scene continues to grow. Barely a week passes without news of new megagames, often experimenting with rules and methodologies for their fantasy, science fiction, or historical settings. If you haven’t tried one yet, there’s no better time to start playing.

Paul Dean is a co-founder of, video personality on, and resident bear lover for board gaming site Shut Up & Sit Down.