The world is invaded by Beasts that inject crystals

A highly skilled swordsman and martial arts fighter,who's intelligence is unpredictable and fierce.He is often silent and only reacts to danger but has highly enhanced sensitivity and Reflexes.He is a Sneaky and crafty human being.He wields sword that is charged by a laser that contains a crystal full of energy surge to cut through hard objects but at a cost of the crystal that can only be found within a beast.He also wears a black hoodie to be Slightly undetected at night and two knives as back-up weapons.Z seeks revenge on the Head beast behind the invasion.