As you travel through The Galar Region, there will be a chance that a Wild Pokemon will have a Pokemon Mark when caught. Pokemon Marks act a lot like Pokemon Ribbons do, being found in a Pokemon's Summary Page and having the ability to be attached to a Pokemon. Wild Pokemon can have Pokemon Marks naturally, but certain Pokemon Marks have a higher chance of being found on a Wild Pokemon when said Pokemon is captured in a certain place or during a certain time of day.
Unfortunately, Pokemon Marks don't really have that many effects to them. Actually, the only thing they really do is give a Pokemon a tagline when sent into battle with Pokemon Marks attached to them. Each Pokemon Mark will look different in a Pokemon's Summary Page, so it comes at no surprise that each have a specific tagline they give to a Pokemon.
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