So supposedly no Pokemon is evil, yet it seems that quite a few Pokemon out there have no qualms against hurting humans in various ways. Hell, the Chandelure line will drain your life force, steal your soul and kill it with fire! Kyurem was rumored to eat people. Hypno...actually, let's not go there.
Anyways, what Pokemon strike you as the most notable in their eagerness to harm humans? You don't have to just go by the Pokedex and the main games, you can also cite other media, like the anime, the manga etc.
IIRC, isn't the only reference to "no Pokemon being evil" just something that a random NPC said? Possibly preceded by an "I think"? I don't remember it ever being stated by the developers, or even said in-game without it being worded as opinion. Basically, it's about as true as shorts being comfortable and easy to wear (and they aren't!).
That said, in the first episode of the anime, Ash nearly relives a scene from The Birds, compliments of Spearow. I might remember that wrong. XD