Nightwing

Richard John "Dick" Grayson was a circus acrobat, the youngest of a family called The Flying Graysons. A gangster named Boss Zucco killed Grayson's parents by sabotaging their trapeze and equipment. Batman (in his identity of Bruce Wayne) was investigating the crime and took Dick into his custody as legal guardian. He trained him physically and psychologically so that he could be his assistant. Wanting to avenge his parents' deaths, Dick assumed under Batman's tutelage the identity of Robin, the Boy Wonder, helping to take care of the streets of Gotham City. Together they investigated the case of the parents' deaths and caught Zucco. Soon after he would form with Speedy (Roy Harper), Kid Flash (Wally West), Wonder Girl (Donna Troy) and Aqualad, the group of young superheroes called the Teen Titans of which he always stood out for being the leader. Robin was improving his detective and martial arts skills during his years with Batman and the Titans. By spending so much time with the Titans, Robin begins to move away from Batman's methods; Dick could not be as cold as Bruce, causing conflicts between the two; Dick opted to leave the Batcave and the Robin suit forever. Jason Todd would become his successor as Robin. Assuming his identity of Nightwing, Dick Grayson would continue to lead the Titans; falling in love with his fellow titan Starfire. After a few years of relationship in which he almost got married, Nightwing separates from Starfire and retires from the Titans to return to Gotham City where he helps Bruce Wayne regain the identity of Batman, which was given to the vigilante Azrael, who was insane. During that time Dick and Bruce resolve their previous conflicts and trust each other again. After winning the final confrontation and knowing that he is not yet fit to fulfill his mission, Bruce Wayne gives Dick the opportunity to be Batman; in this way he fulfills the dream of all.