Four of the five new Union leaders have carried out Master Ava's final order. They all rendezvoused at the Keyblade Graveyard after the war to introduce themselves to one another as instructed. So far, the arrivals consist of Ephemer, Skuld, Ventus, and Brain. The group has already made their first impressions, so all that's left to do is wait for the final leader. The problem is they've been waiting for a while now, and their fellow has oddly still not made an appearance.
The significant events of Kingdom Hearts Union Cross quests 661 through 675 follow the life of a Keyblade wielder named Strelitzia. A series of events happen to her that majorly impact the meeting between the new Union leaders. Essentially, while the Foretellers had a traitor among them, the new leaders will have an imposter and a potential murderer. This writing will act as a recap and interpretation of these events to clear up what's going on in Kingdom Hearts Union Cross, so expect spoilers ahead.
Strelitzia
Strelitzia has a secret. She knows the protagonist, but the protagonist doesn't know her. In fact, through sheer coincidence, they're the one constant in her life. Two years ago, when the Foretellers started recruiting, she found a spot atop a roof overlooking Daybreak Town's Fountain Square and made it her own. She must have seen the protagonist from here every day, but she never really took notice of them until they became a face separate from the crowd one early morning.
Strelitzia saw them standing around waiting for someone, and when she got back from her mission that night, they were still there — waiting. Obviously, whoever they were supposed to meet never showed up. Seeing the protagonist's Chirithy having to comfort them is something that stuck with her. From that moment on, she noticed them everywhere she went, Agrabah, Beast's Castle, Castle of Dreams — everywhere. Her friends would come and go, but there the protagonist was.
These mostly fortuitous viewings of the protagonist gave Strelitzia insight into them. She's even aware they grew tired of doing everything the Foretellers ordered without the full truth. She knows them, yet, despite crossing their path countless times, she's never shared a conversation with them. If she had the opportunity to go back and change that, she would. After nearly two years, she had a lot she wanted to discuss but could never work up the courage to say hi.
She did try once — at the end. Master Ava had indirectly given her an excuse to when she approached her about the end of the world. That night, Strelitzia sat up in her plant-strewn apartment with her Chirithy discussing the situation. She wanted to warn people but knew the majority wouldn't believe her. It was then, Chirithy tried to comfort her by saying her friends would survive since they were Dandelions, and Strelitzia realized that the protagonist was no such thing.
She didn't know what to do at first. She wanted to warn the protagonist, but she had no idea where they lived, and it was the dead of night. No matter how much she frantically paced her room, contemplating how to find them, she couldn't do it in these circumstances. So, instead, she forced herself to sleep, hoping to wake up early and catch the protagonist in Fountain Square. When she did, she would use her new privilege as a Union leader to recruit them into the Dandelions.
Shockingly, however, Strelitzia is killed before she ever sees the protagonist again. That next morning, while she waited in the park, the protagonist learned of the Lost Page from Gula in his storage house. She rushed to meet them after Chirithy saw them in the area, but when she entered the building, it was so dark it appeared empty. It was when she turned to leave that it happened. Someone fatally struck her and stole the rulebook denoting her a Union leader. Before disappearing, Strelitzia managed to carry herself and Chirithy to the light of the entrance, all the while dwelling on never being courageous enough to speak to the protagonist.
The Fifth Union Leader
The last leader finally arrives. After waiting for what seems like forever, someone approaches Ephemer and the rest of the group. He apologizes for keeping them waiting; he lost track of time searching for something. In a reveal almost as surprising as Ventus' Union Cross debut, the wielder introduces himself as Lauriam, a name that when anagrammed with an "x" becomes "Marluxia," the future Lord of the Castle and Organization 13's Graceful Assassin. Judging by his appearance, Lauriam is Marluxia before he lost his heart.
Union Cross, Devourer of Nightmares
Now that they've all assembled, the Union leaders start setting things into motion according to their rulebooks. Their first act consists of telling the Chirithy to implement Union X [Cross] missions, which send groups of wielders after powerful, singular Heartless. After that, the quintet makes its way to the Foretellers chambers for the first time to discuss their next moves. It takes a moment for Skuld and Ephemer to realize everything in the tower belongs to them now, but Brain wastes no time rifling through whatever he can grab.
Skuld suggests the group's next action be to split the Dandelions among them, but Ephemer's viewpoint changes her mind. He understands the rules say to do it, but they don't specify when. So, for the time being, he would like to keep everyone as one Union to avoid once again creating loyalists, which is something Skuld, along with everyone else, can agree with. Ephemer also recommends they tell no one about their new positions to avoid questions about the Foretellers and, inevitably, the war. They'll just relay their orders through the Chirithy.
It's Brain who finally comes up with a task the group agrees on. While poking through the Foretellers' things, he found a book explaining how to synthesize Spirit Dream Eaters. They're not as powerful as Chirithy, but they can devour nightmares, which will help with suppressing memories of the Keyblade War. Thus, he suggests the group create one for each Dandelion. Ephemer, Skuld, and Ventus gather the necessary materials while Brain and Lauriam work on the actual synthesis process. It takes some time, but eventually, every wielder gets a Spirit, and the protagonist's nightmares stop.
Stopping the protagonist's nightmares was the main reason Ephemer and Skuld agreed with the mission. The protagonist's Chirithy told them about the dreams when they ordered it to initiate Union X. Ephemer and Skuld are not only friends with the protagonist, but they know they'll need to rely on them in the future. The darkness of the new world they all live in feels more complex than that of the old one, almost like it has its own will. It's led Ephemer to distrust the Union X missions, but Skuld doesn't think they should worry the Dandelions over anything until they get a better idea of what's going on.
Kingdom Hearts Union Cross is on Android and iOS.