Despite being based on a Mature-rated video game franchise, most of the violence here is pretty tame, since the show was made with children in mind. There is a good deal of martial arts-style fighting, including some inhuman, supernatural attacks, however no extreme violence is ever featured. There is no major blood/gore. Some characters are implied to die/have died, however the deaths are almost never shown on screen, and the few that are generally are non-violent. Even though a good portion of the show is about action/fighting, the activity is never glorified. Characters are fighting for the defense of their world, not personal gain.