The Ogre of Fire was a villain in the children's holonovel series The Adventures of Flotter, from the chapter "Flotter, Trevis, and the Ogre of Fire". He lived in a giant floating castle and threatened to burn down the Forest of Forever. (VOY: "Once Upon a Time")
Neelix read the story about the Ogre of Fire to some telepathic Brenari children in 2375, but they kept reading his mind and preempting the story. (VOY: "Counterpoint")
The Ogre of Fire was voiced by an unknown actor. Its physical representation was computer-generated.