Phantom Trader
Danny's been Ghost King for a few centuries now, he's gotten the Realms to be a better place after Pariah's reign, and he's gotten most of his paperwork done and bored out of his mind. This leaves Danny with the idea that he should visit a world for a few decades and be something he's seen in some video games he's played, a Trader, but not an ordinary one, a Trader that helps both sides, as in his time as Ghost King, he's learned that to be the protector of Balance, he needs to be the Bad Guy at times.
He asked Clockwork if his idea wouldn't affect the timeline of any dimension, and he was told that one such dimension wouldn't be affected at all, which makes Danny happy. He is sent to that dimension to set up what he has planned, he can't be too ambitious, as he is in a dimension that's still in its late 1900's and getting to the early 2000's, and what he has planned is a luxury cruise ship that will house him and his Ghostly Staff and offer 'Back Door Deals' to those with enough money.
He doesn't learn what dimension he's in until he sees the name of a specific family on his guest list one year, The Wayne's, who have a 7-year old Bruce with them when they do arrive on his ship, he knows he shouldn't interfere with the fate of the Wayne's, but he does bond with Bruce a bit during their time on the ship, and offering a friendly hand to the Wayne's before they depart.
The day comes when the Wayne's are killed in that alleyway, and Danny hears about it from the Shades, his main source of information gathering, and waits for Alfred to call. Alfred does call, and Danny has offered to help him and Bruce in any way he can.
When Bruce is sent on his way to learn under the League of Assassins, Danny slowly starts to get customers from them, mainly Talia, Nyssa and Ra's or those associated with them. He is asked what his connection to the Lazarus Pits is, well, more like threatened, he isn't fazed by the threats and handles the Assassins around him easily, he leaves Ra's and Talia for last, having them both subdued when it's their turn to be dealer with. This causes Danny to be considered a potential candidate for the League of Assassins Demon Head when Ra's and Talia are let go.
The years go by and Danny gets more and more customers that are big names in the DC universe, Lex, Diana, Oliver, Slade, Bane, Penguin, Falcone, Waller, Shiva, and others, he is still frequently visited by the League of Assassins, not allowing Talia or Nyssa to get close to him, and not allowing them to get any of his DNA to be cloned with. Croc has become part of his Security Force after he thought that Danny's Ship would be easy pickings, the Drakes are also frequent customers, he isn't seeing Tim with them, so he hopes the Drakes suffer on one of their little archeology digs.
Danny is also the one to bring Jason closer to Ethiopia, sending the boy off with words to try and sway him to wait for Bruce. It doesn't work and Jason still dies in that warehouse, so he plans something for the Joker when the Clown eventually takes his ship on the way back to Gotham.
Danny does feel it when the reality event happens that revives Jason, and he goes to the boys Grave, calling Bruce to meet him there. He does bring the boy out of his grave just as Bruce arrives at the place, being around Danny is keeping the Boy cognizant, but he will be catatonic when Danny leaves, so he offers a Ghost Doctor to treat Jason until he cam be on hos own again, completely free of charge, since Bruce has been a friend for awhile.
Danny does also help with world ending threats, stating that 'If the world were to end, then I can't do business'.
Danny isn't surprised to see Talia on his ship again, he knows what's going to happen, he feels Damian nearby, but he doesn't do anything about it, just offering the services as usual, but he can't wait to see what kinds of animal related things the boy will ask of him when Damian eventually reaches out to him, like all of Bruce's other kids.