Johnny desperately trying to blend in in his old body is hilarious. He just wakes up without access to his powers for some reason in this weird ass cult and being called "Jason"
So he does what any normal ghost would do.
Pray that they don't figure out you're not Jason and just do what they say until you can regain your strength and bust out of here or until the kid manages to find you.
A year or so flies by, and he managed to Somehow someway managed to scramble and accidental himself into being good enough to escape and flee to this random town.
Johnny clumsily throwing some sharp object only to hit it dead on, making flips mid air and SOMEHOW landing on his feet, being able to feel accurately when he's being stared at and where. Johnny chalks it up to luck but something in him cries that it's anything but.
The shadows never felt more like a home to him than before.
Some random things seem to trigger him for reasons he could almost remember but not quite. And all it does is make him angrier.
The MOMENT he sees Joker though, he remembers his death clear as day. Getting beat almost to death and then getting blown sky high. His skin still feels the burns and for the first time in a while his core ROARS
He may be an asshole but all these people just make him SICK! How come no body helped him?! How come HE was the only line of defense against THESE FREAKS?!
"Why me?!" His core screams. "I'm just some guy that likes motorcycles and being cared for, why am I the one that has to suffer through this?!"
And then Batman appears in front of him. And in a click. He's Johnny again, not some child soldier that died, just some guy that's in DEEP SHIT right now with the equivalent of the kid on a bad day WITH STEROIDS AND A BAD FURSUIT that's right in front of him!!
So Johnny r u n s. He runs as much as he can and next thing he knew, his core acts up and makes him invisible and intangible for the first time in over a year, and he manages to get away.
Wait HE'S A CRIME LORD NOW?!
Kid please come pick me up, I'm scared right now!