In the void between worlds that Discord called home, he sat there ponderously. Or floated rather, there wasn't really anything to sit on. He could have done his usual shtick of summoning forth some object, but fiddling about in this realm tended to have 'unexpected consequences.' For the moment he was content to wait and watch, Batmite had promised quite the show and he wished to see it all.
From what he could see Screwball had a classic plan, hijack the weather factory and alter the machinery to start pouring out cotton candy clouds with chocolate rain. A noble effort but without the chaos field that he himself generated such a wonderful sight would be impossible. "Oh well," muttered the trickster. "The game isn't watching an imitator of me at work, it's watching them beat the snot out of each other."
"There's another game we could play as well." came the squeaky little voice of his co-conspirator. "How's she doing?"
Discord waited for him to fully materialize before answering, anything else would be rude. "Good, good. She's halfway to the weather factory already and she's ditched that pesky tracker. Wait. What do you mean 'other game?'"
"Just that, we shouldn't be doing this. Screwball's a pony with rights and we're-"
"Screwball is my plaything. The little fool is devoted to her 'daddy.' I'm merely giving her some purpose in life."
"She had purpose in life before you robbed her of it." Batmite snapped back at him like a vicious turtle.
That raised a furious laugh from the draconequus’s belly. "Doing what, being a house wife to a stuffy business pony?"
"Yes! That was her choice." Now came the tricky part. On a scale of power he wasn't sure who was the alpha, himself or Discord. If he didn't handle this right he'd be finding out real soon. "I want you to fix her."
"My dear imp, she's perfectly unsound the way she is."
"I want you to give that mare back her sanity, you've already hurt her more than anyone ever should."
"Oh ho, that's rich coming from the one who talked me into reactivating her in the first place. I was content to let her decay into nill before you came along."
Batmite was truly offended by his statement, "You, you really don't care about anything other than yourself do you."
"I'm an amoral psychopath who gets his kicks from spreading chaos. Whatever gave you the impression that I care?" Batmite didn't have an answer.
"Fine, you’re a bastard, I'll concede that. But there must be something that will make you want to cure her, anything?"
Discord his placed claw to his goateed chin, "Well, I suppose the only reason we picked her in the first place was for convenience's sake. After all's said and done I care not who our little bat is fighting, just so long as he is fighting."
A thought occurred to Batmite, a thought he knew he would come to regret later. "I propose this, why settle for the bargain bin Joker? We can have the genuine article."
"Really?" The manipulator was intrigued, "You would unleash him on this world?"
If Batmite were capable of sweating he would be swimming in his suit right now. "Yes. Just so long as you do as I ask and cure Screwball."
A devious smile inched across Discord's facial features, "Well I could, but what would that do for our little story we're weaving? Wouldn't it make more sense for little Bruce to be the one to save her?"
"I suppose, how would he do that though? I thought your powers were beyond any pony magic."
"Oh they are, I assure you. But there are artifacts like the Elements of Harmony that can circumvent my power. I know of one that would suit the situation nicely."
"So, I return to Gotham and retrieve the Joker and in return you will give Batman the artifact he needs? Do we have a deal?" Batmite held out his gloved hand for a shake, 'Oh I'll bring him into Equestria you monster, but nowhere you can get your hands on him.'
Discord shook on it with his eagle talon, crossing this fingers of his paw behind his back. 'I'll give it to him, but only if he makes a sacrifice no 'hero' ever would.'
After shaking for a good couple seconds both took an imaginary step away from each other. Neither taking their eyes off the other, "Alright, I'd better be off, I expect to see Screwball happily reunited with her family by the time I get back."
"I'm not a miracle worker imp, but I'll try." He waved him off, once the mite was gone from the formless realm Discord returned to watching the Batman. "Oh you poor little pony, I can only imagine what this will do to your conscience. It's a good thing I don't have one then isn't it? Bwa ha huh ha!" Discord chortled. He would have to begin planning how exactly he would tempt this hero.
Great now Batmite is showing his morals. Seriously bring the Joker here is only making things that much more dangerous. Batmite is jumping down a very slippery slope here. I now fear for Silver Spoon because Mr. J does not like competition for the bats affection. Now I also fear The League of Shadows will be showing up with its leader whose name is escaping me at the moment.
This kinda is giving me the vibe of "author-wasn't-entirely-sure-if-Screwball-made-the-best-Joker-replacement-but-it's-too-late-to-change-that-set-up-so-insert-Discord-Ex-Machina". But I'll grant that it is a fanfic thus being (mostly) written as we go, so I can hardly complain about bends in the river when I made the choice to get on-board.
Now we just have to consider which Joker and from when and how many memories he has.
6547918 I will admit that's partially how this came about. Also I came to a realization that I didn't truly want to start having stories with the joker quite yet, but it was too late to go back and change stuff. But I'll just say this ark has been planned from the beginning, it was just supposed to take place way down the line originally.
greaaaat, that'll mean Harley will tear apart the 5th Dimension (mostly by hammering Mr. Mxyzpltk until he gives her access) to go after her Puddin'.
and Honestly, Discord, if you think you can manipulate the Clown Prince of Crime... Joker will stitch you up so much that he'll be Symmetrical
6550935
6550956 It's the most accurate interpretation I can think of.
especially if Pony!Bruce still sounds like Kevin Conroy, then Pony!Joker is Mark Hamill.
that means TAS and Arkham apply Poifectly
6551376 Well I'm not quite sure which iteration of the Joker will be here. Maybe not anyone in particular, I'll probably be relying on the assistance of my editor who's much more versed in Joker-isms than I am.
6561786 There won't really be anything to reform. More Bruce trying to save his best friend from madness. Anyway that story ark is still far down the road.