The gang is called I Lavoratori Di Babbo Natale.

Giorno Giovanna wanted to become the new Santa after he heard that Santa was giving out coal out to everyone instead on presents

His stand, Christmas Experience can give presents and joy. But it can also beat up people with coal.

Stand cry: COAL COAL COAL COAL!

Bruno Bucciarati was apart of Santa's Workshop line. He also knew that Santa was giving out coal. The only way to get close to Santa was to become an elf leader.

His stand Wrapping Fingers can wrap and unwrap anything.

Stand Cry: MERRY MERRY MERRY MERRY! Merry Christmas.

Fugo was raised by parents who didn't believe in Christmas. He joined Bruno's gang since they believed in Christmas. But because of his parents, his stand was not jolly at all.

His stand Coal Smoke instantly puts coal smoke in you and kills you.

Stand Cry: NAAAUUUGHTYYYYYYYYYYY

Guido Mista killed people because they hated Christmas. He joined Bruno's gang to make himself happy

His stand Elves on the Shelves can stock anything into anything. Even the coal from Mista's gun.

Stand Cry: STOCK!

Narancia Ghira was outcasted because he thought that Santa could change. But no one believed him.

His stand Dashing Through the Snow shoots tiny bits of coal at high speeds.

Stand Cry: Singing the entirety of jingle bells super fast, ending with "Jingle all the way"

Leone Abbachio gave his friend a heart attack when he said he didn't care about Christmas. Because of this, he joined Bucciarati's gang and cared about Christmas.

His stand Christmas Carols replays all past events, but the person it acts out sings Christmas songs.

It turns out that Santa wasn't Santa. He was actually Grinchavolo!

Grinchavolo's stand, The Grinch skips any jolly Christmas event.

After Bruno died, Giorno had acquired The Requiem Bread Man

After eating it, his stand evolved into The Christmas Experience (Or Christmas Experience Requiem)

The Christmas Experience/Christmas Experience Requiems ability puts you on the naughty list. Forever.

"You will never be on the nice list."

Stand Cry: COAL COAL COAL COAL!

Aaaand that's the end. Special thanks to @JustCIaire for helping me with the ideas. We planned this since August.