A knife includes a handle, a blade and a trigger. The handle has an internal cavity containing a compressed gas source and the blade is affixed to the handle. The blade has an internal bore running along a longitudinal axis from the handle to a point proximate a tip. The blade further has an aperture extending from a first edge to the internal bore at an angle relative to the longitudinal axis of between 15.degree. and 75.degree.. The trigger has a depressed position and a not depressed position. When in the depressed position, the internal bore communicates with the compressed gas source and when in said not depressed position, the internal bore is blocked from the compressed gas source. When a creature is pierced with the knife, the trigger is depressed injecting compressed gas into the creature greatly enhancing the incapacitating effect of the knife.