The ornamental design for a boardgame, as shown and described.
FIG. 1 is a top plan view illustrating a board game showing my new design;
and,
FIG. 2 is a right side elevational view thereof; the left side elevational
view is a mirror image of the right side elevational view; the front and
rear side elevational views are identical to the right side elevational
view.
The bottom of the board game forms no part of the claimed design.