Terriermon started out as a wild Digimon, living by the doctrine of "survival of the fittest" in the harsh realm of the Digital World. It Came From the Other Side When Henry received a Digimon video game as a present from his father, he selected Terriermon to play with because he identified with him. During a battle between Terriermon and Gorillamon, Henry caused Terriermon to Digivolve into Gargomon, but Gargomon lost control of his powers and was nearly unconscious when he degenerated, encouraging Henry to regret Terriermon's digivolution. Soon after, the mysterious Blue Card was discovered among Henry's card collection. Henry swiped the card through his card reader, transforming it into a D-Power. Terriermon then Bio-Emerged into the Real World as Henry's partner. Because of Terriermon's near-death experience, Henry strongly discouraged fights, even against attacking Digimon. However, when they needed to protect a child from a rampaging Musyamon, Henry learned that there were some things worth fighting for, and eased off.
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