"Beyond the next Beyond!"
Fengo was the head chieftain of the dire wolves in the land known as Beyond the Beyond during the times of The Legends of Ga'Hoole. He was a very good friend to the Spotted Owl, Grank who, under his tutelage, became the first collier. It is revealed in Wolves of the Beyond that Fengo is a gyre soul, and after his death he went on to be reborn as a bear, an owl, and another wolf.
Before the Books Fengo led the dire wolves from their ancient homeland, the Distant Blue, because of The Long Cold, a time of decreasing temperatures that were inhospitable. He claimed to have followed the spirit of an ancient Hoole and that spirit led him to Beyond the Beyond where the dire wolves would reside forevermore. It was so named because whenever those who followed him asked when they would reach their destination, Fengo would simply reply, "Beyond the next beyond!". It is revealed later that his mate, Stormfast, died during the journey. He named one of the sacred volcanoes in honor of her.
Fengo presided over the dire wolves in the fiery Beyond and studied the volcanoes of the Sacred Ring and also the embers that came shooting out of them. He also possessed the ability to read flames. He was also aware of the nature of the Ember of Hoole. He first met Grank when he came to visit the Beyond to study the flames. He understood immediately that Grank had come to study fire and that he was a flame reader like himself and could see the Ember of Hoole that appeared in Fengo's fiery green eyes. From that point on, Fengo taught Grank everything that he knew about fire, from the individual nature of the volcanoes of the Sacred Ring to the properties certain materials exhibited when they came into contact with fire. Under Fengo's tutelage, Grank became the first collier. At times, Fengo noticed Grank becoming distracted by the Ember of Hoole and criticized him because of it. He also informed Grank that it was the owl ember, not the wolf ember like others thought. Fengo recounted the journey he had made with the rest of his kind and how he was lead by a spirit of an owl, a Hoole to be exact (the wolf word for owl). He theorized that it was the spirit of the ancient Hoole, the first owl to exist when all bird species were being distinguished. Later when Grank retrieved the Ember of Hoole, Fengo showed little rejoice in Grank's achievement knowing too well that Grank could not handle being in its presence for long. Fengo even abandoned Grank after attempting to get him unfocused on the ember. Eventually, the arrival of Joss helped Fengo to break Grank out of his stupor. Grank asked Fengo what should be done with the ember but he simply told him to put it back and when he did that he would find himself.
When Hoole led the dire wolves to the Desert of Kuneer to eliminate the hagsfiends there, Fengo commanded the wolves with Hoole, but he was maimed by the Hagsfiends, who ripped out an eye, and he died of blood loss.
When Faolan visits the Cave Before Time after the earthquake, he meets Fionula, Eo, and, at last, Fengo. They walk together, and only then does Faolan realize the wolf he once was was the first Fengo himself.
Fengo, as a teacher, is firm but gentle. He is quick to be annoyed when those around him pursue trivial matters or are ignorant such as when Grank became engrossed with the flames of the ember to the point that he hardly responded to anything else.
In Guardians of Ga'Hoole, he is mentioned to be silver, but in the Wolves of the Beyond he is black.