My longest ever boss fight was in Baten Kaitos for the Gamecube. It was, for those people that haven't played the game, a card based combat RPG and was one of my favourite RPGs of that time along with Tales of Symphonia and Fire Emblem: Paths of Radiance.

So the boss fight was a battle aboard a ship and is against 3 enemies which are Giacomo, Ayme and Folon. The battle was pretty long as it is, even if you're really good at the game and understand what is going on. On my first play-through I had absolutely no clue what was going on and how to approach the battle. If I remember correctly you have to fight these guys a few times throughout the game but this one was particularly brutal for me. I remember fighting the battle over and over again and the thing lasted about 20-30 minutes each time I tried (depending on my luck with card draws). Eventually I worked out the system to defeat them which, avoiding spoilers, involves attacking 'A' first and then 'B' and finally 'C'. In this way, over time, you find the whole thing much more manageable and avoid some devastating special attacks which may come from attacking 'C' first. There were other such benefits to the system which I only realised through a LOT of trial and error such as healing being cut off for them and such. In all this battle probably cost me about 6-7 hours or so of my life, if not longer. The battle itself, when finally completed, was around 40 minutes. I would readily recommend the game but be prepared for some tough stuff if you're terrible at card games like I am.

If we're talking about one specific battle, though, then I'd have to say the Wesker hanger fight from Resident Evil 5. I could not for the life of me get that guy to stay down. When I play this game now I beat him in like 30 seconds flat, but that's because I know with surgeon-like precision where to be and when. When I first played I was shooting off RPG's this way and that and not understanding why the fool was all 'Neo' on me. Still, I got the last laugh there...

Hyz.