In the best of times, a board game can provide hours of entertainment, filled with camaraderie and tests of wits and guile, thrilling twists of fate and daring acts of strategy and, of course, friendly competition. But a game also comes with a note of danger: Throw yourself into it too deeply, and it’s easy to blur that line between the game sphere — where attacking, undermining or stealing from your loved ones is not only acceptable but encouraged — and the real world, where it is decidedly not.

Taking a game too far can have consequences for one’s real life, including but not limited to tears, profanity and even the establishment of long-running, relationship-threatening feuds: In 2016, the British branch of the game manufacturer Hasbro set up a hotline to help mediate family disputes sparked by its most contentious product, Monopoly. Thank goodness for hindsight, which can paint even the most contentious of quarrels with a comedic lens. After all, it is only a game.

An Incredibly Ridiculous Word

“Za. Who knew two little letters could start such an argument,” Ana Mundaca said. She was playing Bananagrams, a word-tile game, with her grandparents and aunt at their kitchen table in Manhattan when her grandfather exclaimed “Bananas!” and started to read out his words. “They were all fine,” Ana recalled, “except for an incredibly ridiculous word: Za. He claimed it was slang for ‘pizza,’ but it wasn’t in the dictionary and abbreviations aren’t allowed.” So what did Ana’s family do? “We got into a screaming match about it like any other self-respecting family would,” she said. “We eventually did make up and have dinner. But we didn’t order any Za.”

The Real Traitor

Cristeta Boarini can never look at Shadows Over Camelot the same way again. Players of the game work together to complete quests, but if a player draws the Traitor card, then their goal is to use deception to thwart the knights. During one game night, “my husband’s best friend was drunk and accused me of being the traitor — and no one came to my defense,” Cristeta said. “Even after it was revealed that his girlfriend was the traitor, the guy couldn’t help but shout ‘Cristeta is still the real traitor!’ I was furious and ended the evening right there. It is one of my favorite games, and it’s forever tainted by this jerk.”

The Victorious Uno Queen

“You’re sleeping on the couch tonight,” Danya Issawi said. Her boyfriend had just played a Skip card on her in Uno for the fourth time in a row — after changing the color to yellow, which she had none of, and adding about 20 more cards to her hand. Normally, they both toed the line between competitiveness and good sportsmanship, but they were going on their fourth week of self-isolation in a small Manhattan apartment, and this was the biggest event of their week. “It’s just a game,” he told her. So Danya started cursing. A lot. Her boyfriend started laughing. A lot. She started cursing more until, Danya recalled, she found herself at a complete loss for words. “I gave him the silent treatment and only regained sanity when I overthrew his lead and came out the victorious Uno queen,” she said.

As Shifty as Possible

In his early 20s, David Shadburn and his friends loved playing One Night Ultimate Werewolf, a Mafia-esque game in which villagers try to find the werewolf and their cronies before they slaughter the town. Players are assigned roles via a deck of cards; if you draw the Tanner, your goal is to look as guilty as possible in order to get yourself killed. David couldn’t afford an actual deck, so he took a stack of business cards and wrote the roles on them instead. When the cards got worn, he could replace them with fresh ones. One of David’s roommates in Washington, D.C., Harry, hated Werewolf. One night, after begrudgingly playing a few rounds, Harry announced that he was sitting the next one out. “We drew our cards and started to play, and everyone began acting very strange,” David said. They kept changing their stories, trying to seem as shifty as possible — all while Harry watched from the other side of the room. After about 15 minutes, they figured out what had happened: Harry had swapped every single card in the deck for the Tanner. “I was so angry, but it was also really funny,” said David. “Our friends still talk about it to this day.” And he ultimately invested in a real deck, so Harry couldn’t pull that again.

Truly Ruthless

When Bethany Burtch was a child, she learned how truly ruthless her family could be over a game of Spoons, which involves swapping cards to collect four-of-a-kind and then snatching spoons from the center of the table before the other players. “In one haunting fight, my father and 16-year-old cousin both reached for a metal spoon and wrestled each other to the ground,” Bethany said. “In another round, he elbowed a different cousin in the ribs. A third cousin lost all but one of her press-on nails. Oh, and we were all together celebrating Christmas at my grandparents’ house.”

Michael Angelo

In the game Infinitum, players list things that fit into a category. If any answers are duplicated you cross it off your list; if a word is questionable, the other players can challenge it and put it to a vote. During a girls trip to Pensacola, Fla., Nikki Carter and her friends came to the category “Famous Michaels,” and one of her pals wrote down “Michael Angelo.” “I said no, obviously, and the majority of the group agreed with me,” Nikki said. “My friend was so mad that we had to stop the game. Three years later, she’s still polling people at dinner asking them to take sides.”

Pandemonium

Over Chuseok, a Korean harvest festival, Woojin Lim’s extended family gathered in Vancouver to play Yut Nori — a traditional Korean board game that involves throwing four sticks in the air, like dice, and moving pieces around a board based on how they fall. His older relatives bet food, money and small prizes to make it more engaging for the children. At one point, a piece was eliminated before it got to the finish line, and “the entire room broke out into pandemonium,” Woojin said. “Some kids cheered, while others cried. The adults decided to split the prizes among the kids to make them happy. I don’t think we’ve played Yut Nori since.”

All-Out War

Aleyah Llovet’s boyfriend was sitting pretty, with a five-game winning streak in Settlers of Catan — a strategy board game — against her and his cousin. But they battled back, racking up seven and 12 wins respectively. “This led to an all-out war,” Aleyah said. “My boyfriend stole ports and roads, blocked my numbers and eventually drew a card that led to a random victory point to win the game. We were so furious with his lack of strategy and vindictive attitude that we got into a cursing fight with him that lasted for about an hour.”

One Excruciatingly Long Game

Kyle Sanok and his younger brother came to both verbal and physical blows during one excruciatingly long game of Monopoly. As the battle stretched into days, Kyle and his brother started hiding wads of Monopoly money under cushions, in drawers and beneath rugs in their Oakton, Va., home to prevent the other from cheating. After weeks of brinkmanship, Kyle’s brother drained his reserves and ultimately defeated him. “To this day, nothing in the world irritates me more than seeing my brother’s smug little grin upon beating me,” he said. “While I have played board games with my family and friends, he is, and will forever remain, my ultimate competition and nemesis, as I constantly seek to avenge that first, drawn-out, nearly-month-long game of Monopoly.”

Danya Issawi and Charo Henríquez contributed reporting.