The Nightmare Before Christmas Mashup Pack was released on December 18, 2018 by Minecraft in collaboration with the movie "The Nightmare Before Christmas."

Official
This Mashup was created by Minecraft.

What is a "MashUp"?
The mashup packages are combinations between Skins, map and a usable texture, all of this includes a mashup package.

My Discord "Mellitos2008"
In case you have any questions or information.

0:00 Equitpment and Construction
3:23 Nature and other things
5:21 Update 1.19 and more
7:33 Update 1.20
10:23 All mobs
14:00 Mobs variants
15:55 Dimensions
17:52 Final