Rex's Z Move had actually attracted the attention of Arceus themself. Gilda was currently undergoing treatment for her injuries, and Lightning Dust while also arrested, was having her wing mended.
"That was not like any Z Move from the video of Z Moves you showed me Lightning. I should know, I memorized the whole thing." Twilight said.
"Of course you would do that." Sunset said.
"But that video I gave you was the one my father gave me. So if Rex's Z Move wasn't on the tape, you have to ask why." Lightning said.
"Because Rex and his father don't exist in this version of events." A god voice said. Suddenly, what appeared before them was none other then Arceus themself!
"L-lord Arceus! You've never made a personal house call before." Lightning said.
"The Arceus from the human world had informed me that Marina had caused that world to start to collapse. Right now, that Arceus is keeping the ones who weren't there when Rex pulled the ones at Canterlot High here in a state of suspended animation at the Hall of Origin." Arceus said. "Marina is becoming too great of a threat to ignore even for me if she's capable of pulling that sort of stunt."
"Starting to wonder if Marina even is an alternate personality of Milissa with how much we've been learning about Marina." Sunset said. "Especially sense, I could sense some kind of...ghostly presence in Marina's voice."
"Something to take note of then, just in case. Regardless, I am unable to interfere at this stage right now. I am counting on you to find a way to stop whatever her big plan is." Arceus said.
"Apperently, Marina wants to start a war against legendary Pokemon. That's what she said to Sunburst in his audio file." Sunset said.
"...Wait, let me listen to this file." Arceus said. Sunset played it. Afterwards, a forelorn expression crossed Arceus's face. "That voice...that's impossible..." Arceus said.
"You recognize Marina's voice?!" Raiden exclaimed.
"That...is not Milissa's real voice. In fact, she's being possessed by the spirit of a Mawile long thought dead: Marina the Merciless Mawile. She was infamous for how she killed her victims. And by now, you know all too well how her victims died; one of you has even found how merciless she really is." Arceus said.
"The animals in the Everfree Forest..." Fluttershy said. "They...they were drained of their blood, and then their bodies were just...left there to rot."
"Exactly. She was so brutal, many humans began to hunt her. For once, that was the one time I was glad humans were there. However, they found her too late: She had met her end in quicksand." Arceus said.
"So, did a version of Marina exist in the human world then too?" Twilight asked.
"I did ask after Marina the Merciless's death; and it seems that a version did exist. However, in the human world, Marina had been successfully captured by the humans, and was personally executed by that world's Arceus in front a gathering of humans and pokemon alike." Arceus said.
"That's it! That's the divergance!" Sunset suddenly shouted.
"I beg your pardon?" Arceus asked.
"I've been wondering for a while what would make our world turn out the way it did from the human world, and what you just said explains it. In one version of events, Marina was executed by a version of you publically after being successful captured and brought to pay for her crimes. But in another, she was lost to a patch of quicksand and thus, humans never would learn the consequence of growing too greedy." Sunset said.
"That can't be everything though right?" Rainbow Dash asked.
"Perhaps. I would need to compare more notes with this alternate version of myself." Arceus said. "For now, there is one more reason for my visit: Rex's Z Move. It was created by the Tapus and authorized by the human world's Arceus. It's called Barrier Breaker. It's a Z Move that upgrades the moves Fient and Brick Break into a super powered attack. This Z Move is super powerful, so safty measures were put in place for commercial use of the Z Crystal." Arceus said. "However, make no mistake: Trying to cast some sort of protection spell against that Z Move is pointless. Unlike most Z Moves which lose twenty percent of their power when they hit a pokemon protecting itself through the means of moves like Protect and Detect, Barrier Breaker acts like a combination of both Brick Break and Feint at the same time. It actually powers up if something is trying to protect itself by doubling it's power. It also powers itself up to double it's base power if the opponet currently has the effects of the moves Reflect, Light Screen, or Safe Guard up. All the while, it not only doubles it's power if these moves are used, but also removes the effects of those moves as well. It's extremely powerful, but after Sparky was calmed down, the Z Crystal was made weaker for commercial use." They explained. Suddenly they levitated a Z Crystal just like the one Rex had to Raiden. "Here. You may take a copy of the Z Crystal for yourself. Raiden has Brick Break, so he can use this same Z Move. Just remember, the day long recharge. This Z Move may prove useful in defeating Marina and knocking her spirit away from Millissa." Arceus finished.
"Thanks you, Lord Arceus. We'll make sure to use this wisely." Raiden said.
"I am counting on you to free MIlissa from the spirit of Marina the Merciless. You must do so before it's too late." Arceus said.
"But...but what happens to Milissa? Wouldn't she be robbed of her childhood?" Sunset asked.
"Not my concern." Arceus said before he disappeared.
"...Welp. This Marina situation just got a whole lot crazier. But also much more serious too. If Arceus of all legendaries is practically asking us to take down Marina and save Milissa from the spirit's grasp, then we need to do everything we can." Sunset said.
"I just remembered something..." Cheif Marison said.
"What's up, Cheif Marison?" Raiden asked.
"You said Milissa had a mega stone on her neck right? I just remembered: Supreme Chief Jackson had given a Mawilite to Milissa on her sixth birthday shortly before...the incident that cost her her mother happened." Marison said.
"Aren't Mega Stones illigal to be used though?" Raiden asked.
"Yeah. But Jackson said there was no way Milissa would dare use something she knew was outlawed. It'd be safter that way. It was meant as just some accessory, nothing more." Marison said.
"...I think I just realized how Marina's Spirit possessed Milissa: The Mega Stone Jackson gave Milissa must have had the spirit of Marina inside of it!" Sunset said.
"YOU MEAN ALL THIS STARTED BECAUSE OF A BIRTHDAY GIFT?!" Pinkie Pie exclaimed before she fainted.
"...She's really passionate about birthday parties huh?" Marison asked.
"Eeyep." Twilight said simply.