Grievous is far more skilled at saber combat ( assuming you are talking about Vader within his suit.) vaders suit will slow him down, however he has the force, so i am unsure.
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Too bad Grievous got pwned. xD
Oh yeah well greivous is the coolest droid in all of Star Wars. why do you think he's the general?
Darth Vader would win. He can use the force.
Darth Vader
Darth Vader would win.
Darth Vader
Definitely Darth Vader
darth vader
Darth Vader.
Darth Vader. He has 'the force' and a lightsaber.
Darth Vader
If Darth Vader had the ring i would say that it would be sauron
I have to say Darth Vader because Vader has the force and can choke Master Chief.
No one. Vader would have to battle himself since Anakin turned into Darth Vader in Episode 3.