Fletch

Only if you don't cheat. My method? Chain pipe, pull 'im in, kick. Dodge a wave of projectiles, repeat. Does about 120(?, can't remember exactly, know it was 100+) damage per try.

Worst boss ever... hmm. It depends. I have one friend (not used to THINKING...) who swears that the final boss of Quake is the hardest ever. I still haven't told him how to beat it it's too funny watching. My personal pick would be Dhaos (Tales of Phantasia). He had a castle full of ninja, then you get the ever-so-fun two form deathstrike. To add insult to injury, the second form can't even MOVE and it wastes you. Unless you level up. I finally beat him at L99. (I'm told typical levels for the endgame are high 80s-low 90s.)

Hardest boss ever: Dark Dream (DQ6). He slew my entire party in a hit. My party was L65. That's something right there.