Susanoo, the Brave-Swift-Impetuous-Male, is born when Izanagi washes his nose during purification after fleeing the land of the dead. Given rule of the sea, he instead weeps for his dead mother Izanami until his wailing withers the land, and is banished. He storms up to Takamagahara to bid his sister Amaterasu farewell, but his stay turns destructive — he breaks her rice-paddy ridges, defiles her hall, and flings a flayed pony through the roof of her weaving house, offenses severe enough that Amaterasu retreats into the Rock-Cave and plunges heaven into darkness. The assembled gods fine him and cast him down to earth.
In Izumo, Susanoo redeems himself. He finds an old couple weeping over their last daughter, Kushinada-hime, soon to be devoured by the eight-forked serpent Yamata-no-Orochi. He hides her by turning her into a comb worn in his hair, brews eight vats of potent sake, and waits for the serpent to drink itself senseless before cutting it to pieces. Within its tail his own sword strikes something harder:
至尾劒刄少缺。故割裂其尾視之。中有一劒。此所謂草薙劒也
“When he came to the tail, the edge of his sword was slightly notched, and he therefore split open the tail and examined it. In the inside there was a sword. This is the sword which is called Kusa-nagi no tsurugi.” — Nihon Shoki, Book I; English tr. W. G. Aston, Nihongi (1896)
He presents this blade, one of the Three Sacred Treasures, to Amaterasu, marries Kushinada-hime, and settles in Izumo as ancestor to Okuninushi. He is still worshipped at shrines such as Yasaka in Kyoto and Hikawa in Saitama.
