Non-Sith who are possibilities include Joruus, Starkiller (he never got to be a Sith Lord, though was an apprentice to a sith apprentice), the occasionally mentioned Jerec (who I think isn't strong enough). Most of the top are Sith, though.
I don't feel that you need to have the Sith title in order to be a powerful Dark Side user. A Sith and Dark Side force user were basically just two different mind sets. One wanted galactic domination, the other wanted only power, but didn't give a damn about the galaxy. I like these lists so far, and I would like to create a top 10 template using everyone's input.
I want to include battles. As well. For example: If I want Reven on this list, I'm going to include his epic dominance over Malak and the mando wars etc.
Dooku was in his prime. Sure he may not have been as fit as when he was young but he never had such mastery with the force. Regardless, Dooku's saber style hardly required him to be in perfectly fit condition to use effectively.
Need I remind you of AotC
YODA: Powerful you have become, Dooku. The dark side I
sense in you.
COUNT DOOKU: I have become more powerful than any Jedi.
Even you, my old Master.
I did mean physical prime not mental prime so sorry about that. About the quote though, Dooku was a liar...he lied about almost everything; even things that he thought were true. He did indeed get beat up by lil orphan Ani, when he could still be debatably considered a jedi. Once again, physical not mental prime, and we could see from the hunch that sidious needed much assistance from the force while fighting. If he just fought straight up like badass sammy jackson then he probably wouldn't do so well. This applies to Dooku because in the fight where he played the amazing headless count, he mostly used his lightsaber. He used his force a bit and that worked out for him well, because he pwnzord Obi. He tried to saber Ani and it didn't work out quite as well, hence, the neckache. What I'm trying to say is, Dooku relied upon his physical prowess more than sidious did, and that's why age deteriorated his skill.
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