So, for the whole seventeen people who played Baten Kaitos Origins... anyone remember the Holoholo Bird?
Now, the boss in and of itself isn't really all that horrible, though it's got its share of annoying abilities. It goes into battle with two chicks; each chick has a five-hit peck attack that it can use multiple times in a row (so those five hits can easily turn into ten or fifteen) and if you manage to kill one off, the Holoholo Bird can simply hatch a new one. Aside from its usual set of attacks, the bird has a move that can give the entire party the "knocked down" status, which delays your turn and can ruin any giant combos you've set up (and in BKO, setting up a massively-chained party-wide combo is incredibly satisfying, so it's all the more infuriating if it gets interrupted). On top of this, the bird and chicks have different elemental weaknesses.
However, this is all manageable except for one thing; this boss fight occurs immediately after the disc change, at which point you're prompted to save the game. Hell, you have no reason to even expect a boss fight; the disc change happens en route to a new town. You have no opportunity to get new equipment or, more importantly, build up your levels if you find yourself overwhelmed.
Me? Yeah, I was extremely underleveled, but I hadn't really had much trouble up until this point, so I'd never given it a second thought. After who knows how many attempts over the course of three days, I finally beat the thing... and the battle had taken forty-five minutes.