Self-Defense - MMA - The Sprawl
Human Weapon: this video tutorial shows you how to do The Sprawl trick. It is defensive technique that is done in response to certain takedown attempts.

Self-Defense Marine Martial Arts - Round Kick Defense
Human Weapon :

Self-Defense - Judo - Okuri eri jime
Human Weapon: This video tutorial shows you how to do an Okuri eri jime. Okuri-Eri-Jime (送襟絞) is one of the twelve constriction techniques of Kodokan Judo in the Shime-waza list.