Building block toy

FIG. 1 is a right view of a building block toy showing our new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a left view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof; and,

FIG. 7 is a perspective view thereof.

The portions of the article shown in broken lines form no part of the claimed design.