Duck owns. He's really an underrated character in my opinion. I think he can be very effective in a defensive mode because so many of his moves, in my experiences, work well as counters. The DM where he juggles the guy in the air on his feet while he spins on his back is just awesome looking! I love the way it just 'grabs' the opponent and vacuums him in, kinda like the Zanretsuken/Geneikyaku in AOF 1 and 2.
If you're asking what the appeal is...well, it's DUCK KING, man!
I...I just can't explain it
.
I've always thought about a KOF team consisting of Terry, Mary and Duck. Or Duck King, Richard Meyer (or Bob Wilson, with Richard as his manager and a background feature as in RB2), and Big Bear.
The connection? All former enemies of Terry who later became his friends.
I'll try to dig the lyrics up to his RBFF song and post them here later (unless somebody beats me to it).
Threat or promise? You decide...
Taiso
"Because of my bloody life, it was no accident that I was involved in the troubles..."