For a pursuit involving hand tools, concentrated blunt force and beer, Stump claims a surprisingly low number of casualties—at least according to its most ardent devotees, whose definition of what constitutes an injury might differ from your own.

“I’ve seen some nails pop out and hit someone in the face, but it’s not that bad,” says Jeremy Dodge, who picked up the game, which requires beverage-wielding players to toss and catch a hammer before slamming it down onto nails protruding from a thick hunk of wood, while working as a camp counselor in New Hampshire. He became such a fan that once, during his time at the University of Vermont, he spent hours using a flimsy handsaw to free an 18-inch-thick stump from a tree that had fallen on the road along his commute to campus, eventually wheeling it back into the dorms on a skateboard.

“No real major issues,” confirms Michael Cohen, a fellow UVM alum and friend of Dodge’s, speaking on the dangers of Stump. A few minor cuts and scrapes here and there were really the worst of it. But a few times over the years, Cohen concedes, he’s seen players miss the mark completely and thwack themselves, and sometimes innocent bystanders, square in the shin. (“But we used to live right next to the hospital, so it was like, ‘Don’t worry, it’s just a walk away,’” he adds.)

These are the risks one assumes when playing Stump. In fact, this modicum of danger is part of the appeal.

Variations on the game, popular among Northeast college students and tailgaters, are many, but a few key concepts are constant. One nail for each participant is tapped in a ring around the perimeter of the playing surface. The objective is simply to whack every other player’s nail down into the wood before someone else gets you; but before you take your shot, you must first flip and catch the hammer with your dominant hand.

Some rules state that fancier flips earn additional strikes, though certain purists aren’t fond of this edit. “I don’t want to sound like a snob, but it’s like the difference between trying to hit a softball and trying to hit a baseball,” says Cohen. “But that’s fine, if that’s the way you want to play.”

Booze cues factor into the game in a multitude of ways. “Blood is a social,” says Clayton Gray, co-founder of The Stump Company, who acquired a real specimen of a stump for his brother’s wedding in 2014. Yes, in-game wounds mean everyone’s chugging, as do metal-on-metal sparks or flying bark. If your nail gets dinged, you’re drinking; drop the hammer at any point and you’re drinking, too.

In Germany, you can find instances aplenty of competitive nail games with names like Nageln, Nagelbalken and Nagelturnier, executed for recreational, philanthropic or celebratory reasons. It also makes for (relatively) thrilling television: See this 2015 “Nagel-Duell,” pitting comedian Elton against footballer Lukas Podolski in a tense nail-off, one of 11 events in a €50,000 charity battle.

Deutschland’s fondness for connecting hammer with head might’ve been the original inspiration for modern American nail games, according to Jim Martin, CEO of the Hammer-Schlagen nail game brand. An entertainment service firm that’s run stations at beer festivals, concerts, carnivals and parties in 17 states (“I’ve done three funerals,” he adds), the company began with Carl Schoene, a Bavarian whose clan emigrated to Minnesota in the 1950s to open Gasthaus Bavarian Hunter, an old-school German restaurant that still exists today.

Schoene, as company lore goes, implemented the childhood “Nägelspiel,” or nail game, that he played in Europe into the day-to-day at the Gasthaus, cleverly associating it with the draining of steins. Groups would crowd around a log, taking turns knocking their nail flush into the wood with a hammer. “The last person standing had to buy the beer,” says Martin. The primary difference between Hammer-Schlagen’s version of the game and Stump is that the former requires you to work down your own nail, while the latter has you working on that of others. This closeness has Martin convinced that the two are linked.

He pins the creation of Stump on one particular individual—who he refused to name—who attempted to monetize Hammer-Schlagen by switching around the gameplay, adding in hammer tricks. Players outside of Hammer-Schlagen’s commercial reach saw this variation, Martin speculates, and began recreating it on their own. “This Stump deal actually came from a fella who stole our trademarks,” he says. “We stumbled on something pretty fun. Everybody wants it and I don’t blame them.”

That’s not entirely true. This past December, he filed a lawsuit in Washington against an LLC accused of “counterfeiting the famous Hammer-Schlagen® trade dress” at a 2016 Oktoberfest event. Martin’s also taken issue with the aforementioned The Stump Company, and with MöbileSchlägen, a New York brand that will introduce a $150 traveling stump alternative to the market later this year.

“There’s no reason we can’t coexist,” says MöbileSchlägen founder Marc Johnson, who adds that his lawyers and Martin’s lawyers have been in contact.