As part of its ongoing efforts to promote every single Pokémon out there, The Pokémon Company has shared special content dedicated to Cyndaquil:
Did you know? Cyndaquil protects itself by flaring up the flames on its back. The flames are vigorous if the Pokémon is angry. However, if it is tired, the flames splutter fitfully with incomplete combustion.
Source: The Pokémon Company
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