Gantz

18

Gantz (stylized in all caps) is a Japanese manga series written and illustrated by Hiroya Oku. It was serialized in Shueisha's seinen manga magazine Weekly Young Jump from June 2000 to June 2013, with its chapters collected in 37 tankōbon volumes. It tells the story of Kei Kurono and Masaru Kato, both of whom died in a train accident and become part of a semi-posthumous "game" in which they and several other recently deceased people are forced to hunt down and kill aliens armed with a handful of futuristic items, equipment, and weaponry.

GantzTheDemon

145

he is rouge helldiver that killed his teammates and wishes to overthrow the super earth government. you just dropped into your mission and he appeared out of nowhere and starts shooting at you.