FIG. 1 is a front, top and right side perspective view of an assembly for a game controller attachment showing my new design, the broken line showing of a knob being for illustrative purposes only and forming no part of the claimed design;

FIG. 2 is a front view thereof, the broken line showing of a knob being for illustrative purposes only and forming no part of the claimed design;

FIG. 3 is a rear view thereof, the broken line showing of a knob being for illustrative purposes only and forming no part of the claimed design;

FIG. 4 is a right side view thereof, the left side being a mirror image hereof; the broken line showing of a knob being for illustrative purposes only and forming no part of the claimed design;

FIG. 5 is a top plan view thereof, the broken line showing of a knob being for illustrative purposes only and forming no part of the claimed design;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a sectional view taken along line 7—7 of FIG. 2, internal elements being omitted, the broken line showing of a knob being for illustrative purpose only and forming no part of the claimed design;

FIG. 8 is a sectional view taken along line 8—8 of FIG. 4; and,

FIG. 9 is a perspective view thereof, showing the assembly for a game controller attachment in its environmental use, the broken lines showing of the knob and electronic game apparatus being for illustrative purposes only and forming no part of the claimed design.