The night was thick with tension as the convoy rolled out across the Nevada desert. Zayden rode with Arcee—her motorcycle form sleek and agile, wind whistling past his ears as they raced across the cracked highway under the stars. Behind them, Bumblebee followed in car mode, with Mikaela monitoring drone relays from Ratchet's portable station stashed in the trailer.
"Remind me again why we're heading to a vault guarded by murder-machines?" Zayden called out over the roar of wind.
Arcee's voice answered through his earpiece, teasing. "Because you said you like living dangerously. Besides, I thought you wanted more alone time."
He smirked, gripping her handlebars a little tighter. "Alone time, yeah—not instant-death vault missions."
"Relax," she replied. "I've got your back, rookie."
That word—rookie—irked him. "I'm not a rookie. I've literally fought Starscream and soundwave-augmented drones in the last week."
"Yeah," she said playfully, "and you nearly got flattened both times."
He rolled his eyes. "Details."
---
They arrived at the entrance to the vault just before midnight. The landscape had shifted—sharp rock formations jutted out like jagged spears from the earth, surrounding a stone archway covered in dust and strange Cybertronian glyphs.
Zayden tapped the Omnitrix and activated Big Chill, his ghost-like alien form phasing through the door. Inside, ancient mechanisms whirred to life—motion sensors, scanning beams, and the unmistakable sound of something massive shifting in the shadows.
"I see them," he said, floating above an ancient chamber. "Three Phaseguards, built like Megatron on steroids. Looks like they're dormant—barely."
Arcee entered behind him in her bipedal form, her dual energon blades at the ready.
"Don't touch anything unless you want to trigger them."
Zayden smirked. "You know me. I never—"
He accidentally brushed a pedestal with his shoulder.
CLANK.
All three Phaseguards lit up.
"—touch anything important," he finished, sighing.
The battle was instant.
The first Phaseguard lunged, swinging a jagged energy staff. Arcee deflected it with a graceful twist, sliding beneath its arm and slashing through its knee joint. Sparks flew as metal shrieked against metal.
Zayden phased backward, returned to human form, and tapped the Omnitrix again. "Let's try someone big."
With a surge of green light, he transformed into Humungousaur, his massive reptilian body slamming into the second Phaseguard, sending it crashing into a pillar.
"Now this is more my style!"
"Less smashing, more strategy!" Arcee shouted, leaping off his shoulder and landing an aerial spin-kick to the third guard's head.
Together, they worked as a seamless duo—Zayden using brute strength to keep the guards off balance, while Arcee struck with precision, disabling joints, sensors, and power conduits. In minutes, the vault was quiet again, the Phaseguards lying in heaps of smoking scrap.
Zayden let out a breath, returning to normal form. "Okay. That was awesome."
Arcee gave him a sideways look. "You're not too bad for a walking science experiment."
He stepped closer, brushing off a bit of dust from her shoulder. "You know… that teamwork thing? We're pretty good at it."
Arcee paused. "We are."
Their eyes met—hers glowing softly, his intense and focused.
And then it happened.
The moment.
Neither of them planned it.
Neither of them backed away.
They kissed.
It was sudden, electric—like a spark arcing between two live wires. Not just a peck, but real—intense, vulnerable, brief. Her hand gently touched his cheek, his arms steadying her waist.
When they broke apart, both looked a little stunned.
"Wow," Zayden breathed.
Arcee blinked, optics adjusting slightly. "Yeah… that's new."
They stood there in the silence of the vault, surrounded by the wreckage of ancient machines, in the afterglow of battle and the soft hum of technology.
"Should we talk about it?" he asked.
Arcee smirked. "Later. Let's find what we came for first, lover boy."
---
Deeper into the vault, they found it—an ancient Cybertronian console humming with dormant energy. Glyphs hovered in the air around it, pulsing as the Omnitrix reacted.
Zayden stepped forward, his hand hovering over the interface. "You're sure this holds the transformation schematics?"
Arcee nodded. "This is it. This is how I gained my human form. Airachnid's after this tech to perfect her hybrid experiments."
Zayden placed his hand on the console.
A rush of data surged through the room, and the Omnitrix lit up like a supernova.
"New DNA sample acquired: Cyber-Organic Hybrid Matrix."
The Omnitrix's core shifted slightly. New symbols emerged. A new mode had been unlocked.
"I can become… a fusion," he whispered. "Half Cybertronian, half alien."
Arcee's expression turned serious. "You're playing with fire now, Zayden."
"I know," he replied. "But if I want to protect this world, I'll need every edge I can get."
She looked at him, then smiled faintly. "Just don't lose the part of you that made me fall for you."
Zayden raised a brow. "So you did fall for me."
Arcee rolled her optics. "Don't push your luck, human."
But she leaned in and kissed him again—briefly, fiercely—before turning away with her blades drawn.
"We've got company."
A warning beacon blinked red across the vault walls.
Outside, drone scouts shrieked across the desert sky.
And from the shadows, Airachnid watched it all unfold.