Susanoo and Orochi
Susanoo, exiled from heaven, comes to Izumo Province (now part of Shimane Prefecture). It is not long before he meets an old man and an old woman sobbing beside their daughter. The old couple explain that they originally had eight daughters who were devoured, one after the other, by the dragon, Yamata no Orochi ("eight-forked serpent", who is said to originate from Kosi—now Hokuriku region). The terrible dragon had eight heads and eight tails, stretched over eight hills, and is said to have eyes as red as good wine. Kushinada-hime ("rice paddy princess") was the last of the eight daughters.
Susanoo, who knew about the old couple's relation to Amaterasu, offers his assistance in return for their beautiful daughter's hand in marriage. The parents accept, and Susanoo transforms Kushinada into a comb and hides her safely in his hair. He also orders a large fence-like barrier to be built around the house. The fence has eight gates, with eight tables placed at each gate and eight casks placed on each table. Each cask is filled with eight-times-brewed rice wine.
Orochi arrives and finds his path blocked. After boasting about his prowess, he finds that he cannot get through the barrier. His keen sense of smell takes in the sake—which Orochi loves—and the eight heads are now faced with a problem. They want to drink the delicious sake, yet the fence blocks access to the sake. One head suggests that they simply smash the barrier, but that would knock over the sake. Another proposed that they combine their fiery breath and burn the fence to ash, but then the sake would evaporate. The heads begin to search for an opening. They find the hatches, and, eager for the sake, they wish to poke their heads through to drink it. Yet, the eighth head, which is the wisest, warns his brethren about the folly of such an act and volunteers to go through first to ensure that all is well. Susanoo waits for his chance. He allows the head to drink some sake in safety and to report to the others that there is no danger. All eight heads plunge through the hatches and greedily drink every drop of the sake.
As the heads finish, Susanoo launches his attack on Orochi. Drunken from drinking so much sake, the great serpent is no match for the spry Susanoo who decapitates and slays Orochi. A nearby river is said to have turned red with the blood of the defeated serpent. As Susanoo cuts the dragon into pieces, he finds an excellent sword from a tail of the dragon that his sword had been unable to cut. The sword is later presented to Amaterasu and named Ama no Murakumo no Tsurugi (天叢雲剣, "Sword of the Gathering Clouds of Heaven", which was later called Kusanagi, "Grass Mower"). This sword was to feature prominently in many other tales.
Read more about this topic: Japanese Mythology