Why does Marill's tail glow in Sun & Moon?

Question

In the summary, when you tap Marill to make it do an attack animation, it's tail glows. This never was talked about in other Regions Pokedexes and Marill can't learn Tail Glow so why does it's tail glow?

Comments

Marill can't even learn Tail Glow :l

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I know right?

Answer 1

I'm assuming that Marill's tail glows simply because of GameFreak logic. I don't think that there's any other explanation as to why Marill's tail glows.

Comments

I guess that really is the only answer.