Deathstroke is back in a big way for Arrow Season 6 The final slot for Warner Bros. Television’s marathon Saturday session at the San Diego Comic-Con was reserved for the grand old man of the company’s superhero line up – Arrow. With its sixth season getting under way this fall, the now venerable-costumed vigilante series — the antecedent of the Flash, Supergirl and the various Legends of Tomorrow — the series has come full circle.