In Street Fighter II, I love to win with Dhalsim and Zangief. People usually assume that Dhalsim is too slow and week to do any damage, but I'm actually quite good with him, so it surprises them when they realize that they can't get past the first half of the screen when fighting me, and if they do, they get nuggied in the head or a double headbutt. Zangief is also fun because people think he will be an easy win, but when you can execute the spinning pile driver and have tricks to get in close enough to use it, they suddenly don't like you much.
I also used to love playing as Pullum Purna in Street Fighter EX Plus Alpha because she has this air throw where she makes an obnoxious giggle as she throws you to the ground. It use to drive my brother insane, so I would try to beat him in matches where I would only use that move. She also has some satisfying throws on the ground as well, like the one where she grabs their arms, then bicycle kicks them in the face. I love how drawn out it is, so it feels extra punishing if a person gets caught in it.
Basically, I like characters that get my opponents pissed off when they lose.
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