Killed the Joker In Joker: Last Laugh #6, Nightwing is tricked into believing that the Joker fed Tim Drake to Killer Croc. Enraged at the (supposed) death of his surrogate brother, Nightwing beats the Joker to death.
In The Dark Knight Strikes Again, Dick Grayson makes three kills instead of one. The premise is based upon Batman firing Dick Grayson years ago. And to seek revenge, Dick starts undergoing gene therapy to gain superpowers. Dick not only cosplays as The Joker but kills the Guardian, Creeper and Martian Manhunter.
Jason Todd's brutal murder at the hands of The Joker is one of the darkest moments in Batman's mythos, but The Clown Prince of Crime may have killed the second Robin to destroy what is left of his conscience.
Nightwing's death at the hands of Damian Wayne's Robin in DC's Injustice comics adaptation is still a controversial subject among fans.
Jason Todd/Red Hood is easily the Most Dangerous, from Raw Power to Raw Skill. Red Hood is a cold blooded Killer, and is easily the most Brutal out of all the Robins.
Nightwing has a long career in crime fighting that has spanned many decades, but one thing that's remained consistent is his fear of failure, which was instilled by Batman.
In New Earth, Dick Grayson was 21 when Jason Todd died. And Jason was 15 at the time of his death.
Dick Grayson was a superhero and protégé of Batman. Grayson first acted as Batman's original Robin before striking out on his own as Nightwing. However, after his accidental death caused by Damian Wayne, Dick became the successor to Boston Brand as the second Deadman, a superhero working from beyond the grave.
This enraged Nightwing who proceeded to beat the Joker nearly to death. It was only thanks to Batman's intervention that the Joker survived, but the act scarred Nightwing.
Deathwing is the Dollotron clone of Nightwing created by Professor Pyg.
Nightwing's sudden death horrifies all the heroes and many of the inmates. Batman himself is utterly stunned, then outraged to the point of shoving his own son aside and ignoring his protests and apologies.
The Second Robin
Jason had his first encounter with Batman when he was a witness to a fight between him and Joker at age fifteen shortly after a successful robbery.
Dick Grayson appeared as the first Robin in 1940; after his becoming of Nightwing, several different youths have appeared as Robin.
How did the Joker traumatize the Robins? In Batman issue 427, Joker beat the second Robin Jason Todd with a crowbar and blew him up with a bomb.
They find that Thomas's body was missing and then get attacked by Scarecrow. While fighting, Nightwing get sprayed by the fear toxin and goes crazy.
While heroes like Nightwing and Red Hood prefer to distance themselves from the role in adulthood, it's continually interesting to compare the differences between each version of the Boy Wonder. Dick Grayson is widely considered to be the best Robin by fans.
Nightwing isn't exactly famous for his villains, but his most ridiculous nemesis is absolutely his evil DC counterpart, Deathwing.
The original and arguably most famous Robin, Dick Grayson was first introduced by Bob Kane, Bill Finger and Jerry Robinson in 1940's DETECTIVE COMICS #38 as a way to make Batman a more accessible character to kids and grow young readership. It worked, nearly doubling the sales of Batman comics at the time.
Robin the Boy Wonder was actually Dick Grayson, the youngest of a family of circus aerialists, who witnessed his mother and father plunging to their deaths from a sabotaged trapeze.
TLDR: Superman didn't save Jason because he was being tortured by Lex Luthor at the time in order for Luthor to create Conner Kent/Superboy. This is why he wants nothing to do with Superboy once he appears.
Though he never voiced it, Batman did privately admit that he didn't go searching for Jason because he was afraid of what he would find. He knew Jason was killing people, and Batman couldn't live with the shame of knowing that he had unintentionally created a deadlier version of Joe Chill.
A Death in the Bat-Family
“A Death in the Family,” which ran in Batman #426-429, hinges on a chilling scene where the Joker ambushes Robin (Jason Todd) and beats the Boy Wonder senseless with a crowbar, leaving him tied up in a warehouse with a bomb.
Dick's immediate reaction to Jason's death was like this: Shock, disbelief and anger for why he was not told. He was at Tamaran at the time Jason died, but that does not excuse Bruce, Alfred or anyone else not telling him immediately after knowing about his return.
In the years since they began working together, the two heroes made quite a mark on the world and were generally considered the two best. Batman loves and respects Nightwing, and he acknowledges that there are a lot of things Nightwing does better than him.