I claim the ornamental design for a marble game, as shown and described.
FIG. 1 is a perspective view of a marble game, showing my new design with a marble aperture in an edge of a wheel of the design shown in a slightly raised orientation;
FIG. 2 is a front elevational view thereof, illustrated with the marble aperture in a forward, horizontal orientation;
FIG. 3 is a rear elevational view of FIG. 2;
FIG. 4 is a left-side elevational view of FIG. 2;
FIG. 5 is a right-side elevational view of FIG. 2;
FIG. 6 is a top plan view of FIG. 2; and,
FIG. 7 is a bottom plan view of FIG. 2.
The broken lines in the figures depict environmental matter and form no part of the claimed design.