Goku needs ssj9 to beat his first form and ssj10 for rest. They fought goku in ssj9 and cellbuzer in first form and goku was beating him. Cellbuzer second form needed both vegeta and xicor in ssj9 full power so i think cellbuzer second form beats ssj9 fp goku(he does not have it its just hypothetical). And ssj10 goku beat cellbuzer final form