The Gravimetric torpedo was a starship weapon created by the Borg Collective and was used by their vessels in combat against enemy starships. The weapon made use of advanced graviton inversion fields to cause gravimetric shear in its target which causes severe structural damage. This made it perfect for use as an offensive weapon when the Borg encountered a race capable of resisting assimilation. (VOY episode: "Dark Frontier") Though they did more damage than a standard photon torpedo, they required far more energy to maintain. (TNG video game: Starfleet Command III)