Lunatia heros (Say, 1822) is a common predatory gastropod in soft-sediment marine environments along the northwestern Atlantic coast. While recognized as a major predator of several commercially important molluscs, little is known about the diet breadth of L. heros and the potential of this species to exploit a broader range of molluscan taxa. Here, using a forensic approach based on beach-collected shells, we document prey species drilled by L. heros in eastern Cape Breton, Nova Scotia, Canada, and compare our findings to those reported in the literature for this species. Our results indicate that L. heros consumes a wider range of prey species than the fifteen currently reflected in the literature. In beach surveys, representatives of twenty of the twenty-eight molluscan species collected were found with beveled boreholes, nine of which were previously unreported as prey items of L. heros. Our findings thus confirm the generalist feeding tendencies of this species and increase the number of recorded prey taxa drilled by L. heros from fifteen to twenty-four. Further studies of the diet, feeding behavior, and foraging ecology of L. heros should ultimately lead to a more comprehensive understanding of this predator and its role in benthic soft-sediment marine environments of the northwestern Atlantic.