Everybody's Mad About Uno

More than 50 years after its debut, Uno has achieved unprecedented popularity among adults, but its resurgence is creating problems and confusions as players disagree on fundamental rules. WSJ, in a fun story [non-paywalled source]: Think politics divides? Try mixing competitors with different views on stacking "action" cards, or getting everyone to agree on the true power of the Wild card. And nobody can seem to decide whether staples of the game of their youth -- like mandating players yell "Uno!" when they have one card left -- are socially acceptable at a bar with strangers. Mattel has responded by actively settling rule debates on social media, definitively stating that stacking Draw 2 cards is prohibited, while simultaneously embracing the game's divisive nature through marketing campaigns. The company's "Show 'Em No Mercy" variant, featuring more aggressive rules, became the second-best-selling card game in the United States last year according to research firm Circana, trailing only classic Uno itself.