"Carolyn, what is this Halloween you speak of? It seems to invoke a sense of joyful chaos." Nighemera aksed, curious about the costumes she saw.

Carolyn's eyes sparkled with excitement as she explained the concept of Halloween to her extraterrestrial friend, Nightmera. "It's a night of supernatural enchantment, Nightmera. A night when humans embrace the mystical and the macabre, dressing up in costumes to celebrate the fantastical and eerie."

Nightmera's eyes widened, her usual aloof demeanor replaced by curiosity and excitement. "That sounds truly fascinating, Carolyn. I can't believe I've missed out on this tradition all these years!"

Carolyn chuckled, her mind racing with ideas. "Well, there's no reason you can't participate now. We should go out into the city, have an adventure!"

A sudden wariness crossed Nightmera's face. "Oh, Carolyn, I am a kwami. I can't just go out in the open."

Carolyn grinned, a mischievous glint in her eyes. "That's no problem, Nightmera. We'll find you a costume that'll keep you hidden among the crowd."

Meanwhile:

"This will be the time. The device will let you enter the human realm and you'll be able to finally steal that Miraculous," Set said with a sinister grin.

"But how can we get it? The human won't give up her Miraculous. We tried every single thing," Leo said, frustration creeping into his voice.

Jenny, always the quick thinker, proposed a new plan.

"It's Hallow's Eve," she said. "The night when everyone wears masks and disguises. We can blend in, get close to Carolyn, and snatch the miraculous when she least expects it."

Set approved of the plan, a wicked smile spreading across his face. "Excellent thinking, my gifted entity. Now, let us proceed. Let the dimensions bow before me!"

As the words echoed, a portal opened up before them, swirling with energy.

Leo and Jenny shared a resolute glance before they stepped into the portal, ready to execute their plan.

Meanwhile:

"Maze of a million twists alright well never find a way out of here." Carolyn said as Nightmera looked around as she whispered in her ear.

"You can always use my powers to escape." Nightemra suggested, Carolyn chuckled.

"The point is to sharpen your mind, not to cheat." The teen reminded her Kwami as the masked creature sighed.

But when she was about to say something shouting came from the next corner.

But when Carolyn and Nightmera saw what the commotion was the sighed shocked them.

Carolyn quickly hid in the maze, her heart racing. "So much for a calm Halloween, Nightmera. Cosmo Vortex!"

Nightmera was drawn into her miraculous, transforming Carolyn into a costume-clad hero imbued with celestial powers.

The ensuing battle was fierce. Leo and Jenny were formidable opponents, but Carolyn fought with the strength and agility granted by Nightmera.

She launched cosmic-powered attacks, defending herself until, finally, she managed to repel the intruders.

Breathing heavily once Jenny and Leo retreated, Carolyn commanded, "Nightmera, Cosmos Disperse!"

Nightmera emerged, looking visibly weakened as she began to collapse in her mid air but Carolyn quickly caught the falling creature

"Are you okay?" Carolyn asked as Nightmera smiled weakly.

"Hu...ngr...y." Nightmera managed to say, exhasuted from the power that was used.

Carolyn quickly found a chocolate cookie - food that rejuvenated kwamis - and offered it to her friend.

As Nightmera munched on the cookie, her energy was replenished.

Meanwhile:

"You fools!" he hissed. "How could you let a mere human and a kwami outwit you? You will pay for your incompetence!"

Jenny and Leo trembled before their furious master, their heads bowed in shame.

"We apologize, Lord Set," Jenny stammered. "We underestimated their strength and resourcefulness. It won't happen again."

Set's eyes glinted with a malevolent glimmer as he plotted his next move.

"See to it that it doesn't," he growled. "I shall not tolerate failure. Prepare yourselves for a new plan—one THAT GET ME THAT MIRACULOUS!"