Honestly, I'd say Brokenstar is paws-down the most EVIL warrior cat villain. He's shown to be immoral in so many ways and has done so many wicked actions on his own accord. And to think he led ShadowClan for moons with that kind of power and cruelty! As far as I can see, all the other villains on the list (aside from the car option, which I don't really understand considering the cars aren't really characters so much as plot devices to begin with) have at least some semblance of an end-goal or a reasoning behind their actions, even if a few of them are very weak and over-reactive. But Brokenstar was practically sinister from the womb, and I think that's what really cements his position as a truly terrifying villain. From apprenticing kits too early and blaming their early deaths on the medicine cat who treated them, to driving an entire Clan out of their own age-old territory with no regard for the Warrior Code or even his own Clan's safety while doing so, it's safe to say nothing is sacred to this wretched leader. As runner-ups, I'd say Scourge, and then Tigerstar.
ok. my answer (answering my own poll XD) is a monster. Reson?: A monster killed SnowFur, witch when SnowFur Died ThistleClaw went evil. And ThistleClaw, Trained TigerPaw(Star), TigerPaw(Star) Was a good cat till ThistleClaw MADE him Evil! and TigerPaw(Star) Atacked Scrouge(Tiny) when he was a kit! And almost Killed him. So Scrouge Had a big Revenge plan, planed for TigerPaw, Witch was Killing him. Witch he did! But TigerStar Corrupeted HawkFrost and made him Evil aswell! BrokenTail(Star) was the only one that wasn't affected by that one event! BrokenTail(Star) was Born Evil. we don't know why he was evil at birth but he was. he emdntly killed his surviving sister! and much others when he was leader! so I think The wrost cat is: ThistleClaw! the wrost answer on the poll: A Monster! The Second Evilst cat: BrokenTail(Star)!
I think Mapleshade, and even though I haven't really read about her yet, I read one of the last chapters of The Last Hope, she killed Spottedleaf. Spottedleaf was a major character throughout the series I've read, even if she was a StarClan cat. This is my opinion.