As part of its ongoing efforts to promote every single Pokémon out there, The Pokémon Company has shared special content dedicated to Diglett:
https://twitter.com/Pokemon/status/1265688937441497088
Did you know? It travels through tunnels that it digs underground. It hates sunlight, so it comes out only after the sun goes down. Around their crops, farmers plant the kind of tree that Diglett like to eat as a way of getting Diglett to plow the fields for them.
Source: @Pokemon
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