RZA, cause without him there is no Wu-Tang and no more than the next two I'll list would have been heard.
GZA....the sharpest MC ever, his lines are tight and so very on point. Def part of the core of the group with....
Method Man......can't deny the personality and flavor. Meth kills rapping in so many ways, anyways who has seen them live knows he brings the heat live.
You're opinions may differ, but the truth is spoken.
I pity the fool who disagrees.