I thought I'd finished this but this one scene kept niggling at me so got written down eventually. Late by one standard but since huge swathes of the echidna New Year outing is my repurposing of a local tradition that runs on a selection of dates from winter solstice through to Hen Galan on the 13th Jan, depending on where exactly you live, I reckon it can stand!
"Shh shush shush," Sonic spun round to deliver this instruction so quickly that the ringing of the bells in his quills nearly drowned out the actual words. Knuckles opened his mouth to point this out but Sonic had already gone on. "You'll wake her up before we even get there!"
"Us?" Knuckles asked incredulously in the first available gap in the conversation.
Sonic grinned and Tails giggled and they both joined Sonic in surveying Amy's house. Knuckles shook the damp, tangled mess of quills and ribbons back off his face, brushed down his snow-wet fur, and waved Sonic forward.
"After you, and on your own head be it!"
Sonic shot him a confident grin and strode to the door.
"Just you pair be ready with bribes and/or menaces!"
Tails raised the sack as best he could and beamed back. Knuckles followed on Sonic's heels out of pure curiosity.
Sonic hammered on the door briefly then cupped both hands around his mouth.
"This is your New Year's waaaake up!"
There was a long pause.
"Is there another verse to that 'let us in song'?" Tails asked but Knuckles had not yet answered when the door burst open and Amy's hammer preceded the hedgehog herself out of the house with blistering momentum.
Sheer instinct, and the sudden awareness that his head was directly in the line of fire made Knuckles turn and swing for it, catching it on one clawed fist with a shock of impact that stung all the way up to his shoulder. He hadn't even seen Sonic move but clearly he'd hit the deck near instantaneously because he was picking himself back up from the cobbles when Knuckles looked down.
Tails stared, wide-eyed. "Uh, so can we come in?" he said, faintly.
Amy glared at them. "I thought you were Eggman come to launch a pre-dawn raid or something! What the heck!?"
She'd let go of the hammer and was alternately wringing and shaking the fingers of the hand that had held it.
Sonic meanwhile, despite having come within a spine's length of having his head knocked off his shoulders, was laughing so hard he could hardly stand.
Amy's scowl deepened. "What are you doing and what in the name of sanity are you wearing?"
Sonic looked her in the eye then fell about laughing again.
"You can... you can... You can talk!" he hiccoughed through another gale of laughter.
Amy's hand closed on the hammer again.
"Woah woah woah!" Tails said urgently and Knuckles raised both hands.
"Get a grip." Knuckles shook Sonic urgently who straightened up.
"Sorry, Ames." Sonic composed himself carefully. "You look very-" there was a stifled sound which was perhaps just a cough in the chilly morning air. "-nice. This morning."
Amy gave all three of them a suspicious look and Knuckles belatedly caught up with why Sonic was so amused by her appearance. Clearly having been roused from deep sleep to a possible fight Amy was flushed and her quills stuck up in every direction. Fluffy pastel blue pyjamas were rucked at knees and elbows and she'd only managed to get one boot on before hurtling to the door.
But made it to the door, ready to face any threat, she had indeed done and Knuckles dipped his head in respectful acknowledgement, ignoring Sonic's smirk.
"We're not Eggman. But if we had been, we'd have regretted it."
He offered it up as a compliment and Amy's scowl lessened fractionally.
"Hmmm," she looked them up and down. "You might still regret it, I haven't decided yet."
"We brought chocolate and we promise not to wreck the place," Tails put in.
"Yeah and Knux has got a song to sing," Sonic was stifling laughter again and Amy looked between them, baffled. "It's a tradition."
"Is it…?" Amy's expression finally tipped over into amusement. "And what about you, Sonic? Any other traditions you're planning on sharing this year? She gave a pointed glance at the mistletoe hanging over her door.
"Hah!" Knuckles gave a bark of laughter and pushed Sonic forward, cheerfully. "On you go, Sonic. We have to trade something to be allowed in after all!"
Sonic spun and gave Knuckles a glare which nearly matched Amy's with his muzzle flushed the same colour as her fur.
"This is an ambush!" he declared. "I have been ambushed. You're all in it together!"
Tails giggled and Knuckles shrugged.
"You picked the door to knock, Sonic. Now hurry it up, our toes and tails are freezing solid out here."
Sonic glared at the pair of then then plastered a bright, if uncharacteristically awkward smile on his face and turned back to Amy…
...and I'll leave it up to the shippers or otherwise to decide what happened next! ;-) I just wanted to write her taking a swing at them! Happy New Year!