As part of its ongoing efforts to promote every single Pokémon out there, The Pokémon Company has shared special content dedicated to Mankey:
https://twitter.com/Pokemon/status/1275110988438798336
Did you know? The smallest of things could cause it to lose its temper. Because it doesn’t hold in its stress, this Pokémon can live a long time. If one gets angry, all the others around it will get angry, so silence is a rare visitor in a troop of Mankey.
Source: The Pokémon Company
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