In Ohio, you can use deadly force when you are in immediate and reasonable fear of life and limb.

Outside of your home or vehicle, you have a legal duty to ATTEMPT to RETREAT. That doesn't mean that you have to turn your back and run away, grovel or beg for your life, indeed to incur one IOTA of additional danger, much less physical harm. You just have to TRY to disengage, if you can do so IN PERFECT SAFETY. If your assailant thwarts that attempt, sucks to be him.

In home or vehicle the standard is the same, except you have NO duty to retreat and have a rebuttable presumption of justification.

If the shooting is justified, neither your assailant nor any other claimants can recover any monetary damages.