with vader being announced for sc4 and vader having a force/psychic battle with mewtwo on this forum i figured he needed a decent test of melee skills.
for the sake of a good fight, vader has his saber, and buffy has her slayer scythe, because its mystical in nature its conceivable that her weapon could deflect a saber blow. and ill split it into two fights, fight 1, vader can use the force, but he cant use it directly against buffy, so no force choking or pushing her, he can however throw other objects at her. and fight two vader cant influence anything with the force other than himself, so he still has jedi reflexes etc, but thats it.
i think it would be an interesting fight, given that by the end of season 7 buffy is highly trained and skilled in multiple forms of armed and unarmed combat, and that the weapon is custom made for a slayer, seemingly enhancing her already formidable abilities.
id say buffy is quicker, not only with her weapon, but at sidestepping, jumping etc, and she possibly could hold up to vaders force and cybernetically enhanced strength. but vader has much more experience, probably more skill and possibly more strength. he might be at a disadvantage with buffy combining her weapon with punches, kicks etc, something vader hasnt really faced before. so who takes it? whose cuisine reigns supreme?