A variant of the Plasma torpedo which can partially phase through a barrier like a shield before detonating. These devices were never used or tested by the Federation Starfleet before the year 2378, when 20 were given to the USS Sovereign after protecting Starbase 12 from a joint-Cardassian/Kessok fleet in the Maelstrom. (TNG video game: Bridge Commander) It seems that phased plasma torpedoes could be fired from a normal quantum torpedo launcher, but this assertion has yet to be verified in canon.