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Treecko is a small, green, bipedal reptilian Pokémon. It has yellow eyes with long, narrow pupils. Treecko's hands and feet each have three digits covered with tiny spikes. These spikes allow it to scale vertical walls with ease. Its stomach and throat are red. It also has a line across on its stomach resembling a pouch. Treecko has a large, dark green tail with two separate lobes that it uses to sense humidity. This ability allows it to predict the next day's weather.
Treecko is a bit of a rarity in the wild, and is more common in captivity. However, when in the wild, Treecko lives inside overgrown forests. It makes its home in tall trees, and will attack anyone that comes near its nest. Because of its territorial nature, it is known to be the protector of the forest's trees. Treecko is known for its calm and collected personality. It will never panic under any circumstances, even when faced with a bigger foe.