Danny has a group of pet rats that he rescued from a lab. They follow him everywhere even as Phantom. Well Danny gets summoned one day and the league is surprised to see the ghost prince with five rats on his shoulders. "What's with the rodents?" Flash asked. "Kinda rude to ask someone about their service animals." Danny replies. The rats alert Danny before he has a chronic pain flare, before he has a tremor, and before he has a seizure. Being electrocuted messed up Danny's nervous system bad enough that he needs to have an alert animal or someone with him at times that recognize when he's about to have either a flare up or a seizure. The league is going to have a refresher HR course about service animals after the threat is dealt with.

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A lot of stories have Gotham being very ectoplasm contaminated second to Amity Park and because of that makes it a perfect place for Danny to go to. But what if while Gotham still has a very high ectoplasm count, the ectoplasm there was actually was contaminated and poisonous to ghosts. Danny only visited once but having what basically is a ghost asthma/allergery attack, made sure to cross off Gotham from his college lists.

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DP and DC separate universes

Danny is not a comic book nerd, he is a space nerd. Give him any topic about space and he can talk for hours on it. Tucker is the one into comics and it mostly horror/monster comics not superheroes. Danny has hardly any knowledge on characters from DC comics. What he knows about Batman came from the Batman Lego movie because that is the movie that was always put on when they had a sub teacher (the sub teacher was a big Batman fan and always raved about how it was the greatest Batman movie). Imagine Danny's superise when he is summoned my a group dressed in colorful costumes and one vaguely looks like Lego Batman.

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Danny shows up in Gotham, punches Bruce Wayne in the face, cusses at him in Esperanto and leaves with no explanation.

Bruce is extremely confused by the mini Jason look alike and weird language that he didn't understand.

Danny was jokingly dared by Tucker and Sam to punch Brucie Wayne and cuss at him in Esperanto. He got his fifty bucks and a pack of like and vinegar chips so he's happy.

The media is having a field day about Brucie Wayne having a new kid/family drama

The kids are laughing at Bruce and making bets on how long until new sibling is acquired.

Alfred is quietly getting a room ready

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Good Fenton Parents...

Maddie and Jack know that Danny is Phantom, they figured that out pretty early. I mean come on they are smart people being scientist who love and know their children, they would notice when Danny starts acting differently. Also Danny is not as sneaky or stealthy as he thinks. They don't confront him about it, they are waiting for him to come to them about it. (Like how some parents know their kid is gay but is waiting for them to feel comfortable to share that part of themselves).

Them going after Phantom is their way of training Danny and spending time with him. They also partnered with the GIW to keep an eye on them to make sure they don't hurt Danny and to have a way in, incase Danny does get caught by them.

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Here's an extremely silly one. The Fenton's find out Danny is Phantom without him knowing. After a fight, they hit him with a stun gun and when he wakes up, he's strapped to a table and fed space documentaries because his parents, panicking that their child is endangering himself as a vigilante, want to shift his obsession to space. They get Lancer in on it too

Danny: When is this gonna end?

Lancer: I don't know, maybe when you ramble on about Pluto or something

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Danny and his family are on a family road trip and make a pit stop in Gotham, Danny had been developing a new shape shifting power and runs into Jason Todd on a snack run at the convenience store attached to the gas station. Danny was going to get some gum because he has the hiccups. Jason sees he has the hiccups and tells him to either take a potassium tablet or eat a banana since they help. Danny nods and goes on his way. A couple hours later Jason suddenly feels like he's on fire and is writhing in pain on his bathroom floor before suddenly the feeling's gone. He gets up and when he looks in the mirror he finds himself with a pair of white tipped cat ears and a tail with a white tip. Jason is now trying to hide these traits from his family and track down the magician/meta that cursed him. Danny is blissfully unaware of what he accidentally did and is enjoying his family vacation

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Danny makes some little stick figure animal desktop pets, with Tucker's help, mainly to help with homework, act as an autocorrect, and serve as something cute. He notices after a few weeks he notices the way they can interact with different things and is impressed (Think of the stick figures from animation vs animator). He decides to let the little group of six come with him in his phone on a field trip to Gotham. While messing around in Danny's phone they manage to some how accidentally air drop themselves to Tim Drake's laptop who ends up bringing them to the batcave and unknowingly uploads them to the batcomputer. Tim and Danny are both currently freaking out for different reasons

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Danny had more consequences of turning on the portal than just becoming a half ghost, it left his human side paralysis from the waist down. Danny nows needs to use a wheel chair as a human, but as a ghost can walk. This helps hide his identity a little bit more.

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An idea I'm currently playing around:

Basically, what if the GIW changed management and instead of being hindrances to Phantom and Amity Park, they decided to help around. Instead of capturing Liminal People, they train them to control the extra abilities that started appearing. Out of everyone else, the most liminal was Danny's Class who apparently have a lot of secrets.

Now enter the Batman Fandom.

What if the Class became Danny's Court and they're rather well known in school as "The Class that always have a messy field trip", then their class managed to win the Martha Wayne Foundation despite making a mess of it. The Head of the Foundation visited, and secrets unraveled.

Like for example:

Star is apparently Star Al Ghul, Ra's Favorite Grandchild (and by extension, Ra's gained many grandchildren much to his delight and Talia's exasperation)

Paulina is a Luthor

Tucker being related to Commissioner Gordon

Sam being Poison Ivy's little sister (half-sister)

Gotham won't ever be the same once the class is finished with their trip

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Fentons are born extremely frail compared to other babies. Fentons are also attracted to women who can kill them because they know that sort of mother would protect said frail babies

... ypu might be onto something

Danny was currently having a really bad week. Some shape shifting ghosts had escaped and decided to rampage disguised as Phantom, ruining his reputation, unbeknownst to Danny, they were hired by Vlad, in his human form Danny spent the week getting crap beaten outta him by bullies since Sam and Tucker were out of town. The teachers hit Danny with the reality that he was failing and his parents made several new inventions that hurt him. Jazz was also being unintentionally annoying and overbearing. He was currently being held down by anti ecto chains that they purchased from the Fentons, by the Justice League who finally decided to show up in Amity after Danny blasted a GIW satellite that was blocking everything. Thanks to the shapeshifters Phantom was viewed as a serious threat. Danny was stressed, tired, and angry, if they want to view him as a villain then so be it. He breaks the chains since he knows where the weak point is and confronts the league

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Danny portaled into a different world and used the most mundane/ weirdest name he could think of.

Unfortunately, he is using a hero's name, and now he is an accidental impersonator

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Danny gets trapped/turned into a book written in ghost speak and ends up in Gotham where he gets found by Damain while in the school library. Damain feels like the book isn't supposed to be there and takes it. As soon as he opens it at home he literally gets sucked inside. He ends up on a hardwood floor of what looks like another teen's room and comes face to face with Phantom the spirit that inhabits/is bound to the book. The ghost explains to Damain that he needs someone to help him reform his connection to the living world so he can protect it. Damain agrees and strikes a deal with the ghost and gets a pale blue crystal necklace to serve as their connecting point, this way Danny can communicate with Damain outside the book and Damain can slowly gain access to Danny's powers and train to use them

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Danny meets Danny!

How great would it be if our exhausted and living confused teen found himself on Danny the Street! Sam and Tucker flipping out over how cool this street is, baffled that they never knew it was here in Amity Park. Danny starts talking to a steam vent, and they go along with it cause they've seen him have weirder conversations before. Danny welcomes the trio to their neighborhood, and they have a great afternoon with a new friend. Later Danny introduced Dani to Danny the Street, and they get along like a house on fire! No not that one, Danny just got excited. Danny becomes a safe place for Danny to run to when he gets outed publicly and doesn't want to deal with the backlash. He knows the GIW is after him, and he suspects that so are his parents, thank goodness that Danny the Street goes where they want, and Danny just loves the Dannizens.

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In the show Danny did not defeat Pariah Dark on his own, he had help. So there is no Danny is the Ghost King by right of conquest.

That being said, when Pariah Dark is defeated all the top ranking ghosts/spirts get together and decided there needs to be some order to the chaos of realms. They form a council to oversee the biggest issues that cause problems for the realms (everything else is left to territories to govern themselves their own way). Danny is not part of the council, while a powerful ghost he is just a baby by their standards. He needs to exists a lot longer and have more experience before he even gets a chance to be offered a spot. But the council does make Danny their messenger (psychopomp) for the living world. They feel he looks non threatening to the living but can put up a fight if the need is there.

One of the first issues they tackle is educating all the newly dead and new dead adjacent entities. This means they pull all of them into the realms to have a check up and crash course. Beings like Grundy, Deadman and Jason suddenly with no warning disappear from the mortal plan, only to suddenly reappear months later with no explanation. It can be dangerous and its not the place for the living to know secrets of the dead.

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Jazz is a mercenary

She needed the money to support her heavily wounded, unconscious brother and her baby sister (who is watching over Danny while she's away)

In the name of family she has to get her hands dirty. Danny is the ghost king, the infinite realms have worlds beyond time and space, which means the dead have no qualms against killing so long as to protect and to keep order in the realms. (she's trying to justify so her mentality doesn't dip)

She has connections with Thalia al ghul because of Lazarus pit. she purchases a crate full of it (viles) and manually distills and purifies it for at least 3 blood bags to give to Danny (she has a separate place for all her mini lab thing)

Thalia repeatedly tries to recruit her but often gets rejected

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