Fiamon is a Vaccine Digimon that was created for unknown reasons. After ZeroDragoramon's death, it's energy was so great a certain amount of Digimon had to be created in-order to balance out the universe. Among the first of these creations were the extremely deadly Stellerdramon and Photondramon, and then later on the creation of others when it was decided those two were unable to keep the power fully balanced. With that, The Grand One created Fiamon, an In-Training Digimon meant to take the place of Chowmon in the new universe that was formed by ZeroDragoramon's death. Fiamon, although it looks somewhat like a Seal, has hooves like an Elk, as it is not an aquatic Digimon even though it looks like it, but actually based more on an Elk rather than what it would otherwise appear to be. The Grand One has made an example that each Vaccine Starter he designed would be based off a prehistoric mammal; Chowmon being based off a Giant Ground Sloth, and Fiamon being based on an Irish Elk. Like Stethadreamon, Fiamon's final form differs depending on gender, as only males have antlers. Unlike BetaBigdramon, it does not gain any cyborg parts in later stages.
Digimon World: Aftermath