In which Dorothy Gale is a problem:
The realms were torn apart by the sudden cyclones.
No one was prepared: Wonderland, the Enchanted Forest, Earth, Neverland, Arendale, Corona, and even Oz—where they came from—were almost damaged beyond repair.
Until then all of the worlds coincided in peace. Trade prospered, relations were maintained, and for the most part, problems were easily worked through, if there were even any at all.
If the people freely offered their unfiltered thoughts, they all would agree that they thought that Wonderland was going to be the place that broke and would start to harass the others.
Not that each realm didn't have their dark sides—everyone did.
Peter Pan is the only one that never ages. He has a tendency to end the lost boys who got too old, as well as the pirates who try to save them. Captain Hook is the only one who managed to escape, but it was at the price of his hand.
Wonderland has the Red and White Queens, sisters who are constantly at war with each other over some sort of event in their pasts. The Hatter refuses to leave his home, devastated after the attack on the land from the Jabberwocky; the Cheshire Cat has disappeared, although rumors have begun to spread that it's preying on innocent hikers; and there hasn't been a new Alice since the old one left.
The Enchanted Forest has her evil queen, Helena, and Rumpelstiltskin. The two have been terrorizing the kingdom sense Helena took the throne. The only way that the kingdom has survived is through the efforts of her people, those who were brave enough to stand against the duo's combined magic.
Arendale's ice queen is still learning the extent of her abilities, which not only caused a catastrophic deep freeze in the middle of their summer but the rebellion of their people. After some convincing, Lumi managed to regain the trust of her people, but not without a price.
Corona harbors the powerful witches Gothel and Rowena, the both of them responsible for the disappearances of uncountable amounts of children. Gothel managed to procure the princess, her healing powers keeping the witch alive until a thief managed to save her.
Earth? It has giants. Ever since Dorothy was taken to Oz by the cyclone, a portal has been open, allowing the foul creatures to descend on their beanstalks and wreak havoc on the towns around them. The original Jack has long been passed, but another stands in his place.
And Oz? Oz may be the worst. After Dorothy returned home, she immediately wanted to come back, her family dismissing her as crazy after she recounted her adventures following the yellow brick road. Glinda, after seeing the girl's distress and pain, decided to bring her back to Oz in an effort to protect her.
And nothing has been the same sense.
Something in Dorothy's heart darkened, and that darkness spread across Oz.
This caused all of the realms to come to a unanimous consensus:
Dorothy. Must. Die.