Non-Lethal Damage

Nonlethal damage The core rules reference:

The attack penalty for making a nonlethal attack using a lethal weapon is doubled to –4. The penalty for making a lethal attack using a nonlethal weapon remains at –2.

Attacks, spells and other effects that deal blunt, cold or mental damage (and no other damage types) has the nonlethal trait.

''This means that you do not need to take the –4 penalty to knock someone out instead of killing them if you switch from a sword to a club. Casting Cone of Cold would also knock targets out instead of killing them.''

If you make a lethal attack against a bloodied creature it gains the Vulnerable condition. When a creature is no longer bloodied it automatically loses the Vulnerable condition. When a non-notable creature with the Vulnerable condition reaches 0 hp from nonlethal damage it makes a flat DC 15 check: success it’s unconscious and stable; failure it is dead.

This means you can’t just use a nonlethal attack at the very end of a combat - you need to inflict nearly as much nonlethal damage than lethal damage to safely knock the creature out without killing it.