Polybius is an urban legend about an arcade game that supposedly appeared in Portland, Oregon, in 1981. The story says the game was psychoactive and dangerous, causing amnesia, seizures and hallucinations, and that players became so hooked they went insane, died or vanished. Men in black were said to have collected data on players and removed every cabinet. No evidence exists for any Polybius machine in the 1980s. The earliest known print reference is from GamePro in September 2003, and the earliest online reference is a 1998 page. Researchers link the legend to real 1981 anxieties: illnesses reported at an arcade, an FBI raid on Portland arcades over illegal gambling conversions, and a teenager's death while playing Berzerk. People may also be mixing it with memories of real strange games such as Tempest.

Hampi is a UNESCO World Heritage Site in Karnataka, India, with more than 1,600 surviving remains spread over 4,100 hectares. It was the capital of the Vijayanagara Empire from 1336 to 1565. Travellers from Persia and Portugal described it as a prosperous, wealthy and grand city with temples, markets and farms along the Tungabhadra River. By 1500 it was estimated to be the world's second-largest city after Beijing, and probably India's richest at the time. In 1565 a coalition of Muslim sultanates defeated the Vijayanagara Empire, its capital was conquered and destroyed, and the city was left in ruins. Hampi remains a religious centre, with the active Virupaksha Temple at its heart.