Watch this: Backstab, plot and murder in 15 minutes with Game of Thrones: Hand of the King
Okay, "ruining friendships" might be a bit strong, but things do get heated when we play Game of Thrones: Hand of the King in the office.
It's a tabletop game that works a bit like a competitive sliding puzzle. You and your opponents/co-workers/ex-friends move the Varys tile around a 6x6 grid, scooping up family members belonging to the Great Houses of Westeros. Whoever has the most members of a given House controls it, and whoever controls the most Houses wins.
If it sounds really easy to play, that's because it is. It's also diabolical once you start making short-lived alliances, moving to block your opponents and thinking as many moves ahead as you can without losing the plot completely.
As our resident tabletop nerd, I'm also obliged to mention that Hand of the King was designed by Bruno Cathala, one of the biggest names in board games. Cathala is the genius behind Mr. Jack, Shadows Over Camelot and 7 Wonders Duel. In case you were after some more very, very solid board game recommendations.