Nightwing
Although Nightwing is commonly associated with Batman, the title and concept have origins in classic Superman stories. The original Nightwing in DC Comics was an identity assumed by alien superhero Superman when stranded on the Kryptonian city of Kandor with his pal Jimmy Olsen. Drawing inspiration from Batman and Robin, the two protect Kandor as the superheroes Nightwing and Flamebird. Following the Crisis on Infinite Earths continuity reboot in 1985, Nightwing was re-imagined as a legendary vigilante from Krypton whose story inspires Dick Grayson's choice of name when he leaves behind his Robin identity.
Dick Grayson
Eventually, the original League are restored, and Nightwing departs along with some of his League-although others remain as some of the original team take a leave of absence-although Batman notes that his leadership of the League proves that he is ready for more responsibilities. However, the death of Blockbuster prompts Nightwing to leave Bludhaven due to his crisis of conscience; Blockbuster was killed by vigilante Tarantula and Nightwing did not stop it even when he had the chance to do so. While Nightwing returns to Gotham to heal after assisting Batman in dealing with a series of gang wars, Blüdhaven is destroyed by the Secret Society of Super-Villains when they drop Chemo on it.