Okay, so this isn't as badass as some fights we've all had, but this particular gem stands out as the reason I never finished Final Fantasy 7. I believe my copy of 7 went missing after that, and I just couldn't do it anymore. Also, I'll be defining a new term.
The Blastoise Effect/Syndrome
A somewhat common phenomenon of RPGs, in which your main party, or indeed, one character of your main party, will become so nightmarishly powerful in relation to the rest of your characters, that he becomes the only one who gains experience in combat, or rather, the only one worth bringing into latter battles. This can very easily be seen in the Pokemon games, where the adage comes from, where the starter Pokemon becomes a god among bug types. He might stay as your first party member, or, in the case of other RPGs, relegated to clean up duty. You keep him around to keep the rest of your party alive, or so you can survive an encounter.
This is starting to not become as much of a problem, with some games auto leveling alternate characters if you don't play as them, to keep them somewhere near your main party.
Other Examples of The Blastoise Effect:
Tidus in Final Fantasy X
(by the end of the game, my Tidus was hitting for 100k every time, had Auto Haste, Auto-Regen, and Break HP Limit)
Caim's Sword in Drakenguard
Marche in Final Fantasy Tactics Advance
Enough Dictionary, Here's the Boss Fight
Someone strangely using Yuffie on this bastard, or just in general
I'm not going to have as much exposition on this guy as my last run down(Badass Boss Battles numbah 1
What made this fight hard, for me at least, was my beginner's skills in RPGs. I didn't understand the concept of grinding, hoarding items, or the idea of keeping two save files. So imagine a bright eyed child, running up a mountain, killing some monsters, getting some experience, a few items here and there, and you get to a save point. Save points are always good things right? Well, not if you forget to keep a second save file back a ways. And you see this giant scorpion looking thing near by. Well, the gamer in me says "kill it with sword, and get lootz". While not that hard hitting of an enemy, I ran into the battle with few items, about half HP/MP, and not that good equips. I was resoundingly trounced. So I load my save game, and take a look at what I've got. Nothing. Absolutely nothing. No materia shifting for stats and spells, no items to heal. Nothing. So I look at my party members I can shift in. And, thanks to The Blastoise Effect, my other characters were VASTLY underpowered in relation to my mains. So that idea was scrapped. And then I remembered, Vincent was close to a limit break. So I try again, and fire off Vincent's limit break, Galian Beast. The Beast only has two moves, Berserk Dance and Beast Flare. Both did very impressive damage, and he gained HP! Win-Win! Well, until I find out that Beast Flare is a fire spell, and the Keeper absorbs fire. And you loose control of Vince until he dies. Needless to say, I had to load my game again.
This pattern emerged of attack, die, attack, die. Lots of my boss fights do this. Then I had a great idea. I could retreat. Make it back down the mountain. Heal. Buy items. So I make a break for it. Bamm! Run into a dragon. Run away, keep running. I make it halfway before dying. Load up, hope for better luck. I made it farther this time.
This pattern emerged of run, die, run die. Well I juts put away the controller and went to another game. Then I lost my copy of ff7. So I never was able to beat him, or the game itself. I'm gonna try to this summer. Find FF7. Close Shut the Doors of Oblivion. Finish the Fight.
Alright, I'm done