Volcano

A volcano is a type of mountain existing both in the World of Pokémon and in real life. Volcanoes contain lots of lava, though they are not active over long periods of times. When a volcano is active, lots of lava erupts from it, capable of destroying any nearby vicinity.
The first volcano to appear in the Pokémon franchise is the one on Cinnabar Island. It is dormant in the Generation I games, but some time between then and the Generation II games, the volcano erupts, destroying most of the island.
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