Author's note: As per usual, I will accept constructive criticism.
Inside Arendelle Castle
"Anna, Elsa." King Agnarr said. "Bedtime soon." Iduna finished. "Uh oh! The Princess is trapped in the Snow Goblins evil spell! Quick, Elsa, make a prince! A fancy one! Oh, no! The prince is trapped, too!" Elsa and Anna were playing is snow as their parents opened the door and smiled.
"'Who cares about danger when there's love?'" Anna started making kissing noises. "Ew, Anna, blegh! Kissing won't save the forest!" Elsa said. "The lost fairies cry out!" Elsa made a cute sound before asking, "What sound does a giraffe make?" Anna just shrugged.
"Never mind. They wake the Fairy Queen, who breaks the spell and saves everyone!" Elsa cheered. "And they all get married!" Anna added.
"What are you playing?" Agnarr asked. "Enchanted Forest." Anna responded. "That's like no Enchanted Forest I've ever seen." Agnarr said. "You've seen an Enchanted Forest?" Elsa asked. "Wait, what?" Anna piped in.
"I have, once." Agnarr said. "And you never told us this before?" Anna questioned while putting her hands on her hips, trying to look intimidating, but it came off as cuteness.
"Well, I could tell you now. If you -" Agnarr was cut off when the girls ran onto the bed, with eager faces. "Tell us, now." They begged.
"Are you sure about this?" Iduna asked, uncertain. "It's time they know." Agnarr responded. "Let's make a big snowman later." Anna whispered into Elsa's ear. "If they can settle and listen." The girls immediately silenced themselves. He began the story.
"Far away, as North as we can go, stood a very old and very enchanted forest."
Later
"And that night, I came home King of Arendelle." Agnarr blew out the candle. The girls were in awe. "Whoa, Papa. That was epic! Whoever saved you, I love them." Anna fell backward into Iduna's lap. "I wish I knew who it was." Agnarr said.
"What happened to the Spirits? What's in the forest now?" Elsa asked. "I don't know. The mist still stands. No one has come in, and no one has since come out." Agnarr said. "So, we're safe." Iduna added. "Yes. But the forest could wake again, and we must be prepared for whatever danger it may bring." Agnarr said.
"And, on that note, how about we say goodnight to your father." Iduna said. "Oh! But I still have so many questions!" Anna pouted. "Save them for another night, Anna." Agnarr said as he playfully wiggled her foot and left the bedroom.
"You know I don't have that kind of patience. Why would the Northuldra attack us anyway? Who attacks people who give them gifts?" Anna asked. "Do you think the forest will wake again?" Elsa asked their mother. "Only Atohollan knows." Iduna said. "Ato-who-what?" Anna asked.
"When I was little, my mother sang to me a song about a special river called Atohollan. It's said to hold all the answers about the past." Iduna explained. "Will you sing it for us, please?" Elsa asked.
"Okay. Snuggle close." Iduna lay beside her daughters.
"Where the North Wind meets the sea, there's a river full of memory." She sang beautifully.
Later
"Elsa. Psst. Elsa! Wake up, wake up, wake up!" Anna lightly pushed her sister. "Anna, go back to sleep." Elsa groaned. I just can't. The sky is awake, so I'm awake, so we have to play!" Anna said dramatically. "Go play by yourself!" Elsa pushed Anna off.
She landed on the floor with a thud, then got an idea. She climbed back on the bed and opened Elsa's eyelid. "Do you wanna build a snowman?" Elsa smiled mischievously.
The girls ran down the grand staircase, with Elsa shushing Anna along the way. They soon entered the ballroom. "Do the magic! Do the magic!" Anna begged.
Elsa was about to start when they heard a faint growl outside the castle. "What was that?" Anna asked. "I don't know." Elsa said. They both creeped out of the Ball Room, and through the halls, and out of the castle.
They walked normally through the courtyard but paused when 3 other kids with the strangest outfits ever. They stopped to take a deep gulp of air. "Who are you?" Anna questioned.
The tallest was about to speak when they heard growling and loud thudding. A giant grey monster that resembled a dead samurai with purple eyes was walking towards them. "Run!" The tallest kid ordered. He, Miko, and Raf ran past the kids, but Raf stopped and ran back to the princesses.
"Come on! That thing will kill us!" He gasped. "What?" Elsa asked. She and Anna turned around, and Skyquake was right in front of them. They followed Raf back to Jack and Miko.
"What is that thing?!" Elsa asked.
"Zombie!" Miko shouted. "What's a zombie?!" Elsa asked. "You seriously don't know what a zombie is?!" Miko asked in disbelief. "Hide now, conversation later!" Jack said.
They had to run to the docks, having finally outrun Skyquake. They struggled to breathe. "The best thing about zombies, they're slow moving." Miko panted while imitating a zombies walk she got from watching Walking Dead.
"W-Who are you people?" Anna asked. "I'm Jack." "Miko." "Raf." The kids identified themselves. The princesses introduced themselves too and said they were in Arendelle. Suddenly, music broke the moment.
"What's that?" Elsa and Anna asked in unison.
"Phone!" Jack, Miko, and Raf said together. "What's a phone?" Elsa asked. "What are you, 90?" Miko retorted. "No! I'm 8!" Elsa said. Jack grabbed his flip phone and held it to his ear. "Hello? Arcee?" He tried.
The princesses stared at him like he was crazy. "Jack? Can you hear me?" Arcee said in the normal world. "Nothing." She sighed in defeat. "H-Hello? Arcee? Nothing." Jack graoned. "Gee, imagine that. The fourth dimension has lousy cellphone reception." Miko remarked. "What's reception?" Anna asked.
Miko groaned in frustration. "Wait, guys, guys, guys, the phone rang. We're getting a signal." Jack said. "Maybe the Autobots can't see or hear us, but we can, and your phone rang is because we're not only in an alternate dimension. We must be moving at hyper-speed or something." Raf said. "What's a dimension?" Elsa asked. "I don't really know how to explain it." Raf said.
"Back to the matter at hand: Do you think that they could read us?" Jack asked. "Texting!" Raf suggested. "Text me! If my phone's back at the base, maybe they'll see it." Miko said.
Jack began to text Miko's abandoned phone until Skyquake appeared behind them. "Uh, can you type and run?" Raf asked. The mids ran underneath the Terrorcon as he swiped at them. "Wait, hold on!" Elsa said.
She turned around. "What are you doing?!" Raf asked. "Something." Elsa said. Skyquake was slowly walking towards them. As soon as he was close enough, Elsa raised her hands, and blue streams of ice magic burst from her palms and hit Skyquake in the chassis, turning him into ice.
Jack, Miko, and Raf stared in shock. "Whoa." Miko whispered. But Elsa's attack only made Skyquake angrier. The Terrorcon broke through the ice covering his body, and walked a bit faster. "Uh oh!" Elsa said.
In the Autobot base, Ratchet was figuring out what happened. "We're dealing with fluctuating energy profiles inside a wide distortion field. But, it may be possible to backtrace their coordinates." The medic explained.
Suddenly, Miko's phone started ringing, unfortunately nobody heard it.
The kids were still running from Skyquake. "Deja Vu!" Miko said. "What?!" Elsa asked. "This doesn't look familiar to you guys?" Miko asked. "Not really." Jack said. "Dude, we just ran one big circle!" Miko shouted.
Then, the kids ran straight into something hard and metal. "Owie!" Anna moaned while struggling to hold back her tears. "What was that?" Elsa groaned. It was Starscream's severed arm. "Sweet." Miko said. "It must've gotten trapped in here during the explosion, too." Raf said.
They heard Skyquake roar as he was getting closer. "Well, if it's solid, we can use it." Jack said.
Meanwhile, on the Nemesis
"Uh, Starscream, I don't quite understand how this could have happened." Knockout said bluntly. "And, yet, IT DID! Can you imagine my horror? There I am, minding my own business when MY ARM JUST FALLS OFF! Clearly, Megatron inflicted more damage upon me than you realize!" Starscream snapped before he snarled, "Doctor."
"Well, on the bright side, this provides an excellent opportunity for an upgrade. Let's see. You could go with a Sonic Cannon. It's reliable. Low maintenance. Although it lacks a certain flare. Personally, I prefer the Null Ray. It has just the right mix of flash and firepower." Knockout said, as he brought up a few images of the new arms.
"I DON'T WANT A NEW MODEL! I JUST WANT THE SAME ARM I HAD BEFORE!" Starscream bellowed. "But, Starscream, your equipment is a bit... obsolete. I'm not sure I have another one lying around." Knockout said. "Of course we could try to salvage yours. You kept it, didn't you?"
"It was.. beyond recovery." Starscream stated.
Back in Arendelle, the kids managed to turn Starscream's severed arm onto its side. "Anyone know how to fire this thing?" Miko asked. "What's that red thing?" Anna asked. "It's a missle." Jack said. "What's a missile?" Elsa asked. "It's a flying bomb - look, I'll explain everything later." Jack responded.
"Hey! I don't see a trigger here! How does this work?" Miko asked. "Starscream did something with his fingers." Raf said. The ground shook, and Skyquake was closer. "We have one shot. We need to make it count." Jack said. The other kids hid behind him.
As soon as the Terrorcon was close enough, Jack pulled the index finger, making the rocket disconnect from its user. It soared through the air before making contact with Skyquake, flooding the area with smoke.
"How do you like us now?" Miko asked. Unfortunately, Skyquake was fine. His arm right took all the damage, and it fell off at the elbow.
The kids watched as the digits on the servo twitched, then started moving freely. The severed arm uprighted itself and started chasing them 3 times faster than Skyquake could move.
"Come on, come on!" Jack ordered. Then ran again. "How can a zombie arm move faster than the actual zombie?" Miko questioned. The Terrorcon arm jumped onto a shack and onto the ground again. Waking up a few people in the process.
In the other realm, Miko's phone started ringing again. This time, Bulkhead noticed. "Miko's phone! It wasn't blinking before." He gently opened it. "It's a message: 'IN ALTERNATE DIMENSION WITH ZOMBIE, AND TWO NEW KIDS FROM SAME DIMENSION! HELP!'" He read.
"That doesn't sound possible." Arcee said. "Ratchet, can we triangulate the geographical position of the cell phone's signal?" Optimus asked. "In a parallel dimensional plane?! Let's find out." Ratchet said.
Aboard the Nemesis, Starscream's half of the Dark Energon shard started glowing and warbling. "My Dark Energon shard pulsing? My warrior lives." He said. Knockout came in with a new arm. "Ah, look what I found in storage - what are you doing?!" He questioned as Starscream ripped off the medical cables and moved past him.
"You were right, Knockout. I'm much too attached to my original appendage, I will retrieve it!" Starscream said.
Back in base, Ratchet said, "Now, calculating for relative tome delays and ionospheric distortions, the signal emenated from the exact same location as the original Ground-Bridge coordinates.
"But, we already looked for them there!" Bulkhead retorted. "Perhaps. But not in the correct dimensional phase as their message stated. But, if I can recreate the feedback loop that triggered the event, I might be able to generate a rescue portal, allowing passage from their dimension -" Ratchet started before Bulkhead rudely interrupted. "- back to base?"
"No! We're talking about interdimensional travel here, Bulkhead! Attempting to redirect the vortex trajectory would be far too risky!" Ratchet snapped. "Everyone knows that." Arcee remarked. "If the coordinates are not precisely the same, who knows where the humans and their new accomplices could wind up!" Ratchet finished.
"Wait, we're rescuing the new kids too?" Bulkhead asked. "Yes. If Skyquake is in the dimension with them, then they aren't safe anywhere. We have to bring them here." Ratchet said. "And if we can't get them back to their dimension after, their stuck here."
The 5 kids finally stopped but realized they were running in circles, with Starscream's arm being proof. "D'oh! Arendelle is like one big merry-go-round!" Miko hissed.
Then, another voice boomed. "Skyquake! Your master summons you!" It was Starscream, standing next to a house, which in the normal realm was a large boulder.
The kids hid behind the arm. "How did that freak get into our dimension?" Miko asked. "He didn't. He can't see us." Jack reminded. They heard metal clanging. Skyquake's arm was catching up. "Forget Starscream. We gotta run! Some more." Miko groaned.
They ran towards Starscream until a Ground-Bridge opened. Starscream growled. "A Ground-Bridge portal?" Raf asked. "It's our way out of here." Jack said. "The Autobots saw our text!" Miko cheered. "What? Mine, or theirs?" Starscream wondered before bracing himself.
"If we go through, we leave Arendelle, right?" Anna asked. "We'll also run smack into Starscream. And, if we don't..." Raf said. "We're zombie chow." Jack said. "Option 3: We keep running in circles. Or, option 4: We ditch Elsa and Anna, and Elsa keeps making the zombie angry." Miko said.
"Follow my lead." Jack said. They ran to closer to the portal. Elsa and Anna were hesitant. "It's safe. Trust me." Jack assured.
Miko started stammering as the Terrorcon arm was closing the already short distance between them.
Jack waited, then said, "Now!" They ran and jumped into the portal and ran past Starscream. "Humans?! Where did you vermin -" He stopped when he heard clanging, then Skyquake's arm lunged through the Ground-Bridge and grabbed his face as the portal closed.
He yanked it off his face. "This isn't mine!" Starscream yelled as the arm tried to grab him again. "Unhand me!" He commanded.
Another Ground-Bridge opened, and Optimus Prime, Bulkhead, and Arcee emerged. "Jack, Miko, Rafael!" Optimus said happily.
"Autobots?! Again?!" Starscream tossed Skyquake's arm away, which came after him again. "Requesting emergency Ground-Bridge, now!" He shouted.
Later, in Autobot base
Ratchet was examining Elsa and Anna for any injuries, as Miko was apologizing. "Look, if you're gonna blame anybody, blame me."
"I'm sorry. Could you repeat that? A couple dozen times?" Jack asked. "Miko, what you endured has been lesson enough. We are just glad you are all safe." Optimus said. "Well, what are we gonna do about them?" Raf asked. "We were lucky to open a bridge into this Arendelle realm. But, it might never work again, I'm afraid." Optimus said.
"Are you saying they're stuck here forever?" Miko asked. "Indeed." Optimus said sadly. Hoping it wouldn't be that. "Well, may as well start getting used to them. I'll call Mom and see if she can let them stay." Jack said. "I guess it was a good thing you dropped this. Too bad you didn't get any pictures though." Bulkhead said as he gave Miko her phone.
"Nah, I'm okay. I think after today I pretty much have Zombie-Close-Up seared into my brain." Miko said.
On the Nemesis, Knockout was fixing Starscream's injury. " What happened? Megatron pound you like scrap metal again?" He asked.
"I would rather not discuss it!" Starscream said venomously. "Honestly, Starscream, you need to take better care of yourself." Knockout reprimanded, before asking, "Didn't you retrieve your limb?"
Starscream snarled.
Back in Arendelle as the Sun was rising, Skyquake picked up Starscream's arm, and tried to attach it to his appendage. But his attempts were futile. He tossed it away, and limped toward the castle, to destroy everything inside it.
The arm fell right on top of a shocked civilian.