The battle at the end of Chapter 1 in Final Fantasy Tactics where you finally get to beat the crap out of Algus. That felt sooooooooooooooooooooooooooooooooooooo good!

And I always have to lose to Adel in Lunatic Pandora at least once in each of my FFVIII playthrough if only to point and laugh at Rinoa as I make her suffer for being such an annoying, clingy, spoiled brat.