No one has mentioned or filmed getting attacked by an unknown type of Pokémon yet.

[But he hasn't found any unconscious, injured bodies yet, so maybe that's a good sign.]

Of course, legendary Pokémon can be helpful one day and troublesome the next. Not that it's hardly surprising, when one is so linked to nature or similar worldly concepts. A hypothetical guardian of caves and the underworld could be a guide, or just as easily a threat to all that enter its domain.