While the Nether is a vanilla dimension, Hexxit adds much more to it.
Trees / Vegetation
The Natura mod adds trees and vegetation to the Nether, enabling the crafting of new wood tools and the collection of new berry variants.
All of the Nether trees' woods can be crafted into different planks and sticks; this adds new types of wood weapons, bows, and tools.
Beyond Natura, there are now also many Nether glowshrooms (in green, blue, and purple) and giant translucent Nether glowshrooms.
Ores / Metals
These metals are very strong, and cobalt/ardite require alumite/steel pickaxes for mining. Unlike DivineRPG Nether ores, they do not behave like cacti.
- Tainted Soil - Nether trees must grow on this
- Heat Sand - Heatsand will do 1 point of damage per second to the player if not wearing boots
The Nether, outside of its caves, is now a many-layered dimension. The top layer consists primarily of an uneven layer of Netherrack hills, and digging down beneath it will drop you down to the main layer. This layer in itself is multi-layered, but it has the lava oceans and Netherrack hills by which the vanilla Nether is characterized.
The most prominent new feature of the Hexxit Nether is the generation of Nether Cities. They resemble Overworld Villages but are more complex and larger, with ornate Nether Brick buildings decorated with Glowstone. These cities are essentially massive dungeon complexes, as each building contains multiple spawners and loot. The loot is variable, but most of it is rather valuable (essences, armor, precious minerals) and well worth the excursion.