I'll bring a high quality extendo, just becareful not to get
caught, or you'll have a hard time explaining. Make sure extendo is
long enough so you can subdue your mark safely even if he has a
knife, just don't get too carried away and end up killing
him.
If you can obtain pepper sprays, i would say it's the best option.
It will incapacitate him for long enough to escape. If his face
sucks, don't hesistate to spray more than once on his face. It will
cause him unimaginable pain and suffereing.
However, if your assailant is armed with guns, i would suggest you
apply fast strokes to kill him. Hitting on the left cheeks, temple,
solar plexus, nose bridge with enough force can kill him in one
blow or at least black him out.