annihilate. Killing ends when the thing you are killing (your sworn enemy, all hope, a pesky mosquito) is dead. Annihilate goes farther-when you annihilate something, you wipe all trace of it from the earth. You kill a person, but you annihilate a tribe, a town, or even a species.
Pets can be uselful in many ways! Ane piece of evidence to support this is... (add a moment when a pet have saved a life or a real world use for pets and how they are useful)