Place it near the end of an edit, after the Imperial March has established the threat, so it works as the hero's answer. Follow it with the Mortal Kombat Fatality sound to close the sequence with a decisive payoff.
About this sound
This is a short spoken line lasting just over two seconds, delivered in a young, steady voice that says 'Not today' as a flat refusal. It feels resolute and quietly brave, like a promise to keep fighting rather than surrender. The line comes from Game of Thrones, where Arya Stark learns it as the answer to give the god of death.