The Autobots arrived at the railway, it was just the train with soldiers on board, protecting the destructive device.

Arabella watched through the mirror seeing Bulkhead transformed and shooting at the tunnel entrance so no MECH soldiers could get in then he quickly transformed back to catch up with the others.

Driving along, Arcee and Bumblebee transformed into their bipedal mode as she hopped onto the trailer as Bumblebee leaped onto the train carriage. He knocked on the side which an armed soldier opened the door, allowing Arcee to pass the DNGs to Bumblebee who placed it inside the train.

Both Autobots transformed back to their vehicle modes as presumed driving which by the time they were out of the tunnel, it looked as if the exchange didn't happen ' I really hoped this worked ' Arabella thought.

She watched as a bunch of jets appeared in the rearview mirrors, seeing to all too familiar purple color scheme she has seen.

"Optimus, you have company," Ratchet said, seeing the signals that appeared on the monitor. The Decepticons then fired off missiles at them, shocking Silas.

"Military fired on one of their own?" He asked himself in surprise watching them swerved to avoid the missiles, but the sudden change in direction caused the hitch between Optimus and his trailer to strain. At last, the hitch came loose, and the trailer skidded along the ground to a halt.

"Sir, the D.N.G.S!" The pilot called, as the trailer got caught in the explosion caused by the missiles. "Sir... The D.N.G.S didn't melt down..."

"No." Silas replied in a low voice. "It did not."

Down below, the Autobots came to a halt as the Decepticons transformed and landed on the ground below.

"Agent Fowler. Arabella" Optimus said firmly. "I'm afraid that if you and we are to survive, it has become absolutely necessary to drop our cover."

The Autobots then transformed, with Fowler ending up in Optimus' servo, feeling sick once again as Arabella landed in his other servo.

Above them, Silas watched the scene before him and smirked, "So, the rumours are true." He said darkly. "Living technology stands before us. Though perhaps not for very long..."

"Remain here," Optimus ordered and put Fowler and the young witch on a stack of rocks. "Will do." The man replied as Arabella gripped her wand, ready for the fight.

Optimus walked back over to the others. "After a long road trip, it feels so good to get out of the car, stretch my legs, and kick some tailpipe!" Bulkhead said, transforming his servo into a mace, and charging, the other Autobots following suit to fight the cons.

"Sir..." The pilot said. "If the D.N.G.S wasn't in the truck..."

"Yes," Silas replied. "That." He then activated the radio link that connected with Fowler's radio. "Special Agent Fowler. You lead a charmed life walking amongst titans."

"Come on down," Fowler said sarcastically. "I'll introduce you."

"In good time," Silas replied. "But at the moment, I'm too busy wondering how the D.N.G.S could've vanished into thin air without a trace." He said, looking at the radar, which had a purple dot on it, as it moved along the railway that was nearby.

Arabella thought back, and realized what had happened, " They know what we did "

"Now if you'll excuse me." Silas said smugly. "I have a train to catch." Fowler watched as the chopper headed into the distance.

"Prime! Silas got wise to Phase 2!" Arabella spotted the train which she bit her lips, contemplating her decision, she knew that she could appariate to the train but the high risk of her getting splinched in the process. She only did something like this once and she hoped that lady luck was on her side.

Meanwhile, Optimus was busy fighting when his commlink came on, but this ended up distracting him. A Vehicons had picked up a fallen tree and hit Prime's helm pushing him off the cliff and knocking him unconsious. The 'Cons soon got the upper hand after this, and soon threw themselves on top of Bulkhead, keeping him from moving.

Arabella blasted spells at the Vehicons who were on top of Bulkhead. Fowler spotted her about to Apparate" Arabella! don't..." but his shouting fell into death's ears as Fowler watched his goddaughter disappear, knowing what she was about to do.

"Immobilize them," Silas ordered, and one of the men fired a projectile at the train. It flew through the air and stuck itself on the side of the train cab.

Instantly, electricity was emitted from the device and surrounded the carriage. Because it was made of metal, and because of the close proximity of the vans, the electricity went along the entire train, knocking everyone on board out cold.

The train was now a runaway. Arabella appriated on the train and muttered a shield spell which avoided her from getting shocked by the electricity.

Meanwhile, inside the van with the D.N.G.S, a Groundbridge appeared Jack and Miko tumbled out onto their backs, the bridge closing behind them. "We're in," Jack said as they got up.

"I read you, Jack. The cellphone-comm. link patch works." Raf said from the other end.

The two teens then heard the sound of a chopper above them, they ran over to the door, opened it, and looked out. They could see the chopper landing on top of the van. "Raf! MECH's landing on top of the train!" Jack said.

"In about 20 seconds, you're going to come to a fork. Brace yourselves!" Raf replied and set to work hacking into the signaling system.

The helicopter got closer and closer to landing on the van, but at the last second, the points changed, and the train was switched off the mainline.

The change in direction threw the chopper off, as it hit the top of the van it was about to land on. It spun out, but quickly regained control. Arabella slipped but hold onto the train handles, " ARABELLA! "Jack and Miko hastily grabbed onto her and brought her inside.

" Thanks, guys," Arabella said as they watched the helicopter stabilize. "What happened?!" Silas asked, angrily. "Hacker." The pilot replied. He then pressed a button. "Former hacker."

The chopper landed on one of the vans, and the men began cutting into the occupied van's roof. Jack, Miko, and Arabella looked up as they heard the clang of the chopper land on the roof, and watched as the roof was cut away.

"So what'd that buy us?" Jack asked. "10 seconds?"

"Raf is losing his touch," Miko commented. Arabella steadily pointed her wand, ready to shoot spells at them.

Back at the fight, the Autobots finally got the upper hand. The noise woke Optimus up, and from the direction he was facing, he could see the train below in the distance. His optics widened as he remembered what Fowler had said and noticed that Arabella was gone.

The three teens continued to watch as the roof was cut away. Miko then noticed the emergency axe on the wall behind her and grabbed it. Jack then noticed the fire extinguisher next to him and pulled it off the wall. Arabella's wand was sparking, and she got into her spell-fighting pose.

The roof was finally cut, and the piece of metal fell to the floor with a clang. The men looked inside to see three teenagers inside the van. "You want a slice of this?!" Miko asked, angrily. "WELL DO YOU?!"

"What she said," Jack said, and held up the fire extinguisher.

In the chopper, which had landed on the van behind the one the D.N.G.S was stored, the pilot noticed Optimus running alongside the train near the back.

"Sir!" He called, and Silas looked back to see Optimus, who looked over at them, and transformed and drove alongside.

"Retreat," Silas ordered. The men climbed back into the helicopter, and they took off to the sky once again, flying ahead of the train this time. Jack, Miko, and Arabella then looked out of the van as they watched the chopper take off.

"Woah," Miko commented. "You're pretty fierce." Jack just raised an eyebrow, while Arabella smiled, rolling her eyes.

"First rule of combat:" Silas said, as he picked up a missile launcher. "Never leave the enemy with the spoils." He then leaned out, aimed, and fired. The missile flew ahead and blew the tracks ahead up, destroying them. A column of smoke drifted high into the air as Miko, Jack, and Arabella looked on, terrified.

"Woah!" Jack exclaimed. " We need to get out of here!" Arabella exclaimed.

Jack then looked down at his phone, "Ratchet, MECH blew the train tracks! You need to bridge us out of here! The soldiers too!" Jack said into the phone.

"We've lost access to the train data!" Ratchet replied in a panic. "I can't bridge you back without your coordinates!" The three teens looked at each other in concern, as their options ran out one by one.

Arabella pointed her wand at the train and a silver mist shot out, toward the wheels, trying to stop it. The young witch could feel herself getting exhausted as she puts all her energy into her magic but it only slows down the train only a little.

At the end of the train, Optimus was driving along at the back when a call came in. "Optimus! Jack, Miko, and Arabella are on that train and MECH has blown the tracks! Arabella is trying to stop it, but she can't do it on her own! She needs help!" Ratchet said through the comm.

"I'm on my way!" The Prime responded and activated his throttle. "Maximum Overdrive!" he was worried about the children but his spark was pulsating over the thought of Arabella in danger.

"Maybe we should jump?" Miko asked. "At 90 miles an hour?!" Jack asked in return.

"It's the impact or the meltdown. Take your picks." Miko said, knowing that time was running out. "Ugh... What were we thinking volunteering for this?" Jack asked, regretting his decision.

"Next time, you need to do a better job of talking us out of these situations," Miko said, almost forgetting the life-threatening situation they were in.

"Next time..." Jack muttered, knowing that there probably wouldn't be a next time.

"We can buy ourselves some time if we're in the back of the train, right?" Miko asked, looking out towards the back, before looking back at Jack as Arabella was trying to stop the train, a drop of blood dripped down her nose.

Miko then swiped Jack's phone from him. "Raf, this is important!" She said into the phone, "Make sure Bulkhead gets my guitar."

The three teens looked ahead to see how close they were to the damaged section of the line, but the sound of a loud engine caught their attention, and they watched as a certain red and blue semi truck raced passed them.

"Don't read the will just yet!" Jack said, as they watched on. Back with the rest of the Autobots, they had just finished taking out the Vehicons when Arcee noticed Arabella and Optimus were missing.

"Where's Optimus and Arabella?" She asked. "They had a train to catch," Fowler replied and watched what was happening below but worried for his goddaughter's safety. The Autobots ran over to the edge and did the same, worried about what was happening.

Optimus soon caught up the front of the train and transformed, he jogged up to the front and grabbed on, taking up the strain.

Arabella was glad that Optimus had arrived, as she wasn't sure how much longer she could've held on by herself with the spell. Optimus growled as he dug his pedes into the ground and held the train back.

At last, thanks to their efforts, they were able to slow the train down and brought it to a complete stop just in front of the blown-up track. Everyone breathed a sigh of relief.

Arabella wiped a bit of the blood from her nose, "Oh... that was exhausting."

Optimus looked at the children seeing if they were okay, Arabella smiled tiredly at him as his blue optics soften lightly but furrowed seeing her exhausted state and the nosebleed. Arabella and Optimus looked up at the sound of a helicopter.

"Well played, visitors," Silas said. "But MECH still has the home-field advantage, and we will find a way to level that playing field. Even if it means we have to open you up, to see what makes you tick." The helicopter then took off into the distance, as Optimus and the others watched on.

"Optimus..." Ratchet asked slowly. "Are you and the children... intact?"

"Intact, Ratchet. Crisis averted." Optimus said. "But the world in which we live is different than previously imagined. One which has spawned its own Decepticons.... in human skin."

Arabella soon collapsed which Miko and Jack caught the exhausted witch, feeling her body drained from the magic she used. Optimus's optics widen slightly seeing her collapse form which he gently grabbed her as the Autobots and the humans returned back to base after their mission.

They arrived back which the Autobot medic spotted his leader holding the Scamander witch. Ratchet was already running scans on her, "I'm fine. I just need a minute. It's my own fault, though. I used a bit too much of my magic on stopping the train."

Ratchet graciously took her up from Optimus and headed towards the medical bay. She was sitting in a bed, " Young lady, you would do well to rest." Optimus and the others wanted to check on the femme.

"I will monitor her vitals. Now leave. She doesn't need to be bothered right now." the other children looked at each other surprised at Ratchet's protective state over Arabella but Miko had a different thought and she was hiding her smirk.

A/N: Finally done!!! Sorry for the long update. I am fragging done with this chapter, this was one of the episodes that i didn't really enjoy since it took so long to write and i kept forgetting to finish it!

sorry I haven't been writing, it's just I lost a bit of motivation for this book but now i will try to post but most likely they will be slow updates.

comment below if you guys want chapters ideas or special au's that i should add in :)

Thank You for reading, commenting and voting! Hope you enjoy this tfp x harry potter crossover fanfiction