>>8566661you need to target joints, elbow, knee, wrist, ankle, neck. it will cripple/main the person you hit, so you better be able to prove you are defending against deadly force. also the person will immediately try to grab the thing from you, which gives you time to kick, knee punch. you have a split second to decide to use the weapon, you don't brandish it or display it or threaten. you extend it behind your back (hiding your arm) then you strike in the same fluid motion. three strikes, wrist, elbow, neck. or if you are already on the ground, ankle, knee, neck.
the only knife you should carry if that is legal for self defense is a karambit, which requires you to practice a lot with using it since it's a slashing knife that is concealed, and i would not think using a lethal weapon like that is viable ever, this isn't a john wick movie, but the canadian legal system.