Author's Note: Prompt was an AU where Elsa is left with the trolls as a child and she and Kristoff play pranks on the troll children: here is one such prank.
For your purposes, "Gris" means "pig" in Norwegian.
T-Minus Troll
"Come on…come on…."
Kristoff jostled and shushed her, but she ignored him, her determined gaze focused entirely on the little troll child plodding his way through the forest. Gris was stopping every now and again to stuff his face with dandelion heads and daisies. Food was very important for a growing boy, even if his growth was more horizontal than vertical, and as such he was taking his merry time getting to the cleverly disguised trail they'd spent the morning digging. A morning that had been punctuated by giggles and random shoving while Sven bleated and bounced in between them like the "rowdy scamp" Elsa called him while tugging on his ears.
"He's taking forever…" she groaned, and dropped her head to her knees. Beside her the human boy was worrying a leaf in between his thick fingers as they waited in the bush for Gris to get a move on, but their target was both blissfully unaware of their spying on him and of the timetable he was failing to keep. Sven's hot breath tickled Kristoff's thigh while the three of them crouched, some of them more patient than others.
The troll paused and glanced around quickly. Satisfied that he was alone, he happily lifted his hand to his face and extended his index finger. Elsa let out an "ICK!" before Kristoff could clap a hand over her mouth when Gris' finger left his nostril, entered and then exited his mouth, leaving behind a satisfied smile. He eyed the shaking bush with some curiosity, but when he stepped towards it, his dark eyes bulged and his feet flew out from under him. "Ahhhh!" cried Gris, and thus his rapid descent down the glittering ice slide began. Elsa and Kristoff raced out of their hiding spot and to the top of the hill to watch.
Squealing, the troll boy shot down the hill, made slick with a thick carpet of ice, smashing right through the first layer of glue dripped over carefully arranged branches and into the second within seconds of each other. Next, Gris hit the stolen pillows and they exploded all over him, showering him in downy feathers that stuck to his gluey body. Kristoff and Elsa howled, barely able to stand as they leaned on one another, when Gris shot through the pillowcase filled with red dust, his hacking and cursing music to their ears.
The crashing and screaming came to a complete halt for a single instant when he came upon the ramp leading up to the pool beyond, and for a glorious moment the sun that filtered through the trees in merry beams illuminated Gris' stunned, if upside-down expression plastered to his messy face as the feathers fluttered in the breeze, his body soaring above the gleaming pool, giving him the likeness of an idiotic angel, and the children learned that sometimes, pigs do fly.