When a player falls from an island, they'll leave the Aether and be spawned high above their original portal in the Overworld and fall straight down, so one is advised to put water around their portal or they will die of fall damage. Normal torches and fire cannot be used in the Aether due to the oxygen level being too low, so the player is limited to only using Aether originated items and tools. Normal Overworld tools have extremely low efficiency in harvesting and mining blocks of the Aether, so even using hands to harvest skyroot logs would be faster than using diamond tools. When the player step through the portal for the first time, a portal will spawn in a randomly generated Aether. To get to the Aether, one must first make a Aether Portal formation out of Glowstone, and place water with a water bucket in one of the top corners. There are many new mobs such as Aerwhales and Cockatrices, items and blocks in the Aether, some being entirely different from those in the Overworld, but few are similar to overworld mobs. Its main features are large floating islands and formations of Aerclouds, which are solid cloud-like blocks. The Aether is an inverse to The Nether, with the Aether being large solid areas in empty space while The Nether is empty space in large solid areas.

Via manual installation and previous version-profiles via the official Minecraft launcher.

Via the Technic Launcher's various Aether modpacks.

There is also a +1.7.10 (up to 1.12.2) port of The Aether called Aether Legacy for those looking for an up to date version with extra features, tweaks and fixes.

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