Three Steps of a Dwarf, and the King They Humbled

Vamana is the dwarf, the fifth avatar of Vishnu, and his story is a study in outwitting a good opponent. The demon-king Bali is generous and rules well, that is precisely the difficulty, for a righteous and mighty king cannot simply be defeated in battle. So Vishnu comes to Bali's sacrifice as a small brahmin and asks only for as much ground as he can cover in three steps; Bali, warned but too generous to refuse, grants it, whereupon the dwarf grows until two strides span the earth and the heavens, and for the third Bali, having nothing left to give, offers his own head, and is pressed down into the underworld (patala) to rule there.

The three strides of Vishnu are the one thing the Rigveda actually says about the god, so this avatar preserves the oldest layer of Vishnu's identity showing through. In Kerala the tale is told from Bali's (Mahabali's) side, and the great festival of Onam celebrates the good king's annual return to visit the people he once ruled, a rare instance of a festival honouring the figure the god defeated.