The updated generation of the world not only includes a new height (320 blocks), but also a new system for generating mountains and caves, which additionally received their own biomes! Mountains can have one of five different biomes.
Minecraft 1.18.2 Features World Generation If we talk about coordinates, then the bottom of the world (bedrock blocks) will be at a height of -64 blocks (previously 0), and the top of the world will be at a height of 320 blocks (previously 256). In this second part of the update, the developers from Mojang Studio will make big changes to the game world, for example, the height of the world will increase by 128 blocks, that is, 64 blocks up into the sky and 64 blocks down. Initially, some of the features described below were supposed to appear in the Minecraft 1.17 Caves & Cliffs update, but due to the pandemic, the authors decided to divide the update into 2 parts.