Hito Shura is always the answer to this. I didn't even feel good when I finally beat him... I still felt like I lost. --- Now playing: Pandora's Tower, Mass Effect 3, Halo 4, Fire Emblem Awakening, The World Ends With You
Of course Elizabeth also gets my vote, but I want to do something different, and mention a boss that isn't from an RPG, and isn't a final boss. Fans of the X series probably remember Crush Crawlfish from X3, and probably remember how much damage he does and how easy it was to get hit by him. Even with the special weapon he was weak to, the fight wasn't a sure thing like most of the others, at least in the first fight. Even with the weapon, unless you had at least half the heart tanks, you probably used a sub tank for the fight. Sure, the second fight was no problem when you cut him in two with the Z sabre, but that first time was really something.
Dr. Wily - Mega Man 7 Grim Reaper - Castlevania 1 (most of the final boss battles in earlier installments should be listed here) Jacquio- Ninja Gaiden 1-NES M. Bison- Street Fighter II --- PSN-BruceLee007
Dullahan without summon rushing (Golden Sun: The Lost Age) Magician Faust (Legend of Dragoon) Culex without lazy shell (Super Mario RPG)
I never had any problems with Faust. I was so worried after hearing everything here on GFAQs but my Kongol destroyed him.
Ozma, from FFIX was a total Jon Snow of a boss, but not too hard if you did the quest for his weaknesses.
I would say Armstrong on Revengeance difficulty of MGR:R. Guy is a wild lunatic. Especially since you can't do any real damage to him for most of the fight! --- "i've had sex with a chick who was a psy major, so yeah i think i know what aspergers is" -LiquidFuze180
-That optional boss with over 50 million hp in FF12 -Genshin from Ninja gaiden 2 (also in ninja gaiden 3 trial... I just never seem able catch on to his pattern, and needless to say he's such bad@$$) .. Actually lot of boss are tough in ninja gaiden series -final boss in Zero 3 -vega (claw) in street fighter 2 (CAN'T beat him with anyone except chunli haha)
...I'm sure there are more but those 4 are right off top of my mind at this moment --- exGT-ShadowPHOENIX1 newGT-ShadowMINDGAME1