This datapack adds a new dimension to the game, The Upside Down. To get to this dimension rename a grass block to "Dinnerbone" and then put it in your offhand. Then you will teleport to the dimension. In this dimension you always have levitation, and the "floor" is at y level 210ish. Their is two main biomes, The Rocky Wastes, and The Forest Caves.

The Rocky Wastes:
The rocky wastes is made up of stone and gravel, and vexes and Giant Phantom spawn here.

The Forest Caves: The forest caves is made up of stone on the "floor" (higher y level) and the "ceiling" (lower y level) is made up of grass and dirt. Skeletons, spiders, cave spiders, sheep, vexes, and giant phantoms spawn here. Forest cave spawn upside down trees.

Skeletons have a punch two bow and drop levitation arrows.

Their is two structures that spawn in this dimension: a house and The Yeti Cave!

The house is a small house with a chest that contains: an iron pickaxe, torches, bread, and a miner's helmet. The Miner's Helmet gives you night vision when you use it.

The Yeti cave is a small cave with ice blocks and snow. A yeti has a chance to spawn in it. The yeti has 150 health, deals 6 damage with its fists, and has two special abilities.

It can spawn Mites in waves. Mite can fly and have massive knock back, have 1 heart, and die after 3 seconds.

It can also howl, giving you weakness and dealing 2 hearts of damage.

Killing it drops it's head, and yeti feet. Put the Yeti's head in your offhand to return from the dimension to the overworld, and the yeti feet create explosions when you jump.

Only works in 1.16.1

YT video link: https://youtu.be/mHQ09Bw5wKY