Jason Todd avenges his own death by killingthe Joker, butRobin’s revenge unfortunately doesn’t affect the real Clown Prince of Crime.Jason Todd’s brutal murder at the hands of the Jokeris one of the most infamous deaths in DC Comics history. Apart from marking the death of Batman’s sidekick, Joker’s use of a crowbar was especially graphic for a 1988 comic.
By this point,Jason Todd has long adopted the Red Hood mantleand come to terms with his death and resurrection. Batman has also learned the corresponding lessons from Robin’s death and Joker’s relentless violence. But while Robin’s murder is old news by this point, the Joker is still getting a taste of his own medicine.

InBatman / Superman: World’s Finest#42, Batman, Superman, and Robin learn that another version of Robin killed his own version of the Joker.
Robin Killed The Joker In Bizarro World
Batman / Superman: World’s Finest#42; Written by Mark Waid; Art by Adrián Gutiérrez & Matt Herms
InBatman / Superman: World’s Finest #42, the titular duo and Robin come face to face with Bizarro and Bizarro Batman, who reveal that in their world, Bizarro Robin killed Bizarro Joker with a crowbar. As is usual in Htrae, everything happens backwards. Most iconic events in DC history must have taken place the other way around there.
Bizarro Robin’s motivations for killing Bizarro Joker are unknown.Everything works backwards in Bizarro World, but the exact way “backward” can be interpreted is difficult to predict. For instance, the virus currently turning Htrae’s population “normal” causes its population to seek infection first, as chasing the virus is the opposite of fleeing.

DC Has Already Shown What Bizarro Joker Looks Like
Action Comics #1062; Written by Jason Aaron; Art by John Timms & Rex Lokus
InAction Comics #1062, the original version of the Bizarro virus transformed humans into Bizarro versions of themselves. However,the Bizarro virus had the opposite effect on the Joker, who lost his iconic madness. Considering this reaction, it’s safe to say that Htrae’s version of Bizarro Joker looked and behaved quite similarly prior to his death.
There are many ways Bizarro Robin’s murder of Bizarro Joker may have unfolded. For example, instead of an act of cruelty, the murder may have been viewed as a noble gesture from Bizarro Robin.Bizarro Joker may have done something positive by Htrae’s standards, and Bizarro Robin may have paid back in kind.

Otherwise, Bizarro Robin’s motivation could have been rooted in his loyalty to Htrae’s chaos, believing he was protecting Htrae’s backwards order by stopping Joker’s reasonable mind.Batman / Superman: World’s Finest #41shows just how desperate Htrae’s population feels when they lose their reverse logic. Hence, Bizarro Robin’s crowbar strike may have been an act of duty to maintain Htrae’s wrongness.
