What's a game series that had a continuous story, that across the course of more than one game, seemed to be leading up to an epic conclusion, but the final battle left a lot more to be desired?
I'm going with Jak III. I don't know why Naughty Dog, during the entire trilogy, was so sparse with their bosses. I think there were three in the first game, and only four in 2 and 3. The final boss was so anti-climatic, it isn't even funny.