Ghost King in a world of Injustice
In a battle between Batman and Superman, a Toxic Green portal had opened up near the fighting pair, Superman put some distance between him and it, expecting it to be some sort of Kryptonite related thing to weaken him, Batman put distance between him and it because it is an Unknown and whatever might come out of it may not be good.
What they didn't expect was for a teenage boy to be flung out of the portal and try to go back through it after recovering. He couldn't make it in time. He only noticed them after awhile during his cursing rant to some 'Observants'.
They also didn't expect to call them his Dads and be friendly with them
In this Dimension where Danny has to fight either one of his Dads, he will encounter a lot of Hurt because of his obsession, learning that Lois is dead, Conner and Jon don't exist, and Dick killed by Damian with Tim, Duke, Stephanie and Cass not being part of the Batfamily will do a number on him.
As for the Danny of the Injustice world, he is a full Ghost, Haunting his grave, Metropolis, having been there when Joker detonated the bomb in the city.
Ghost King Danny also has to deal with this world's Fenton Parent's as well, with them having delusions that he is their Danny that has come back to life. But all Ghost King Danny sees is their crazed looks and scalpels and the reminder of his traumatic experience with his world's Fenton Parent's
This is set in the first Injustice game, as that's my only knowledge on Injustice