Ninja Tactics; Where to Strike 101
In the image I provided you can see a majority of pressure points of the human body. These are your targets for a quick and easy takedown. By attacking these points even the mightiest of opponets will be at your mercy. When in doubt remember these words, "If it bends, it breaks.
Watch your opponent and look for signs of additional weak spots. Most of us break something in our lifetime so look for scars and other markings. Aim for bruses, cuts, and sores, it's all fair game in a fight for your life.
Most importantly don't become predictable aiming for just one or two spots. Mix it up and throw in a few shots to the kidneys, shoulder joints, neck, and torso to keep them guessing while doing serious damage.
If by chance you are going for a knock out the head is the obvious place to strike but not always readily available. Try striking right under where the ribs connect to knock the wind out of your opponent to make an opening. This also works by one good shot to the neck, but winding an opponent isn't the only way to set up a knock out. You can attack the back of the leg to topple them over or step into a cross block and come from behind.
Knowing when and where to strike will make you an unstoppable force. Incorperate it all into your muscle memory and double the likelihood of success. The more you practice the more deadly you become.