Golisopod has a Bug type move that is effectively Fake Out without the flinch and only +2 priority and like 80 or 90 BP. So the ability gives it a free one of them if it can be switched back in safely.
And it looks like Wishiwashi is a pseudo-pseudo, like Slaking. It's monstrous but it's ability...
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So, magearna isn't a 100x6 Mythical pokemon? wOt?