The lights of the Nuka-Cola promotional stage flickered to life against the cold steel backdrop of the wasteland’s largest remaining settlement. Snow machines hissed, speakers crackled with cheerful pre-War jingles, and out stepped Lucy MacLean, smiling the practiced, optimistic smile Vault-Tec had drilled into her from childhood.

Her Santa coat was bright red, trimmed in white, and clearly designed for someone who hadn’t been drinking Nuka-Cola as heavily as she had been lately.

Lucy adjusted it as she walked, the coat straining to close, buttons pulling slightly as her body pressed against the fabric. Stockings hugged her legs, heels clicking on the metal stage, and though the outfit was meant to be playful and festive, it was impossible not to notice how much she’d changed. She wasn’t just heavier—she was vastly heavier, her frame softened and expanded in every direction, like the cheerful excess of the old world had finally caught up to her.

A smiling Nuka-Cola mascot waved from the side, holding a banner: “HOLIDAY CHEER TASTES BETTER WITH NUKA-COLA!”

Lucy raised a bottle and laughed, a little breathless. “Turns out… I might’ve tested the product a bit too thoroughly,” she joked, earning applause.

Behind the scenes, Vault scientists whispered. The formula wasn’t just addictive—it was metabolic. Calories multiplied. Bodies adapted. The human form, already resilient, simply… grew.

Lucy didn’t seem upset, though. If anything, she carried herself with the same earnest warmth she always had. She moved more carefully now, sure, but she still waved, still smiled, still believed the world could be better—even if Nuka-Cola was quietly reshaping it, one sponsor at a time.

As snow drifted down and the jingle played again, Lucy lifted her bottle and called out:

“Happy Holidays! Remember—stay positive, stay kind… and maybe pace yourselves with the soda.”

The crowd laughed.

The scientists did not.