Though killed by Superman, the Joker continues to haunt the lives of all those touched by his madness. How he came back will no doubt leave you with question, but this is the norm with comic books.
By destroying Metropolis, he set the events in motion which made enemies of Superman and Batman. If he were alive to see the chaos he’d created, he would surely be smiling.
The trailer shows him kicking the crap out of Superman so one has to think that he has some sort of power now. It also seems they went far for Suicide Squad movie with him, which is something I’m not thrilled with.
Also, his ending pose makes him look like a dweeb.
Injustice 2 drops May 16th, 2017. Pre-order: https://go.wbgames.com/injustice2Buy