Who is your top hated movie villain?

I'm not looking for the biggest villain or most powerful. I am looking for the one you hated the most.

The ones that you can barely stand watching on screen. I'm looking for the Joffrey Boratheon/Ramsay Bolton of villains.

I would have to say the villain I hated the worst would be Dolores Umbridge from Order of the Pheonix. Followed closely by Claude Frollo from Hunchback of Notre Dame. Biff from Back to the Future Trilogy.