Hiawatha battles Megissogwon when his people are plagued with a fever caused by the magician. Nokomis warns Hiawatha that Megissogwon has fiery serpents (the Kenabeek) who protect his waters and that he is full of 'wicked wiles and cunning.' She tells Hiawatha that Megissogwon is the one who sends the 'pestilential vapors' and 'poisonous exhalations' and that Hiawatha should arm himself to save his people and to avenge her father's death.
Hiawatha proceeds to equip himself with his war-gear and prepares to approach the waters of Megisoggwon. When the fiery serpents taunt him, call him 'Faint-Heart' and tell him to go back to old Nokomis, he takes up his war-bow and shoots his arrows, each arrow 'a death song of Kenabeek.' With all the serpents dead, Hiawatha rubs the oil of Nahma on the bow and sides of his boat in order to facilitate the moving of his vessel through the moldy, rotting waters of his enemy's territory. He rows west until he reaches the realm of Megisoggwon. When he lands on dry ground, Hiawatha shoots an arrow with a challenge to his enemy to come out and fight.
The battle lasts for a whole summer's day. We are told that even with his arrows and his war mittens (Minjekahwun) wielding the heavy war club, Hiawatha could not vanquish his enemy, on account of Megisoggwon's magically powerful wampum shirt. In the end, frustrated and weary, he finds help from Mama, the woodpecker. Mama tells Hiawatha to aim his arrows at the roots of Megisoggwon's black tresses on top of his head, for he is defenseless there. Hiawatha does so and dispatches three swift arrows which finally bring the great magician to his knees. After his demise, Hiawatha rewards the woodpecker by dyeing its head with the blood of Megisoggwon; this dyed head becomes an everlasting symbol of the woodpecker's service.
Before he leaves for home, Hiawatha gathers all of Megisoggwon's wealth and his wampum shirt. He leaves the magician's body half buried in the sand and half in the water. Hiawatha sails home exulting
With the trophies of the battle,
With a shout and song of triumph.