Sub zero 'could' be considered bad, as he turned his back on and murdered scorpion. Thus scorpion was sent back from hell to avenge the death of him and his family ( I think ) at the hands of sub zero.
Orochi - King of Fighters 97
Chozo Ghost - Metroid Prime
The Hand - Super Smash bros. / Smash melee
Infu - Soukaigi
Cervantes - Soul Edge/Calibur
M. Bison - Street fighter 2 (The end boss, not the boxer ya JP ver. fans)
Sigma - Megaman X
Olga Flow - Phantasy Star Online Episode 2
Dural - Virtua fighter
Vermillion - Battle arena Toshinden 2 and 3
there is no fighter harder or cheaper than geese howard from art of fighting 2. let's list the details- ground wave, double ground wave, buzzsaw cutter jump that drains 1/8th energy, the ability to recover from most throws, longest spirit and life bar, ability to throw opponent during any time at any move with most priority, the ability to do his panic combo (75% damage) at any time, and a weird energy uppercut that kills in one attack. add to that an annoying taunt that drains most of your spirit and geese is still the ultimate badass. oh, and try fighting him in fatal fury 1, three special moves and a simple pattern, but he will make yuo cry.