Disable the Eye of the Jailer by completing the “Focusing the Eye” quest in Shadowlands.
Shorty after unlocking the ability to use any of your mounts in the Maw you’ll move on to disabling the Eye of the Jailer. Both of these are attached to the new Chains of Domination campaign, and you don’t need to complete the Shadowlands 9.0 campaign or reach a specific Renown Rank to get started.
To start the Chains of Domination campaign, and to ultimately disable the Eye of the Jailer, you only need to complete chapter 2 of the 9.0 campaign, “Torghast.” Once you’ve completed the quest “The Search for Baine” you’ll be given the Chains of Domination introductory quest “The First Move” automatically. This will eventually lead you to Korthia, the new zone added in Shadowlands Patch 9.1.
To disable the Eye of the Jailer in the Maw you’ll need to reach the third chapter of this new Shadowlands campaign, “Focusing the Eye.” This shouldn’t take you more than an hour to reach, and you’ll unlock the use of your mounts within the Maw in the process. Once you reach “Focusing the Eye,” it’ll take you roughly an hour-and-a-half to an hour to reach the final, titular quest of chapter 3.
Take down the Eye of the Jailer by using the spears provided to pull down the smaller eyes guarding it. Kill all six of these to throw a final spear, which will trigger a cutscene. Afterwards turn in the quest to permanently disable the Eye of the Jailer in Shadowlands. This will make the Maw far easier to play within, which is a boon considering how much has been added to the zone in Patch 9.1.
World of Warcraft: Shadowlands Patch 9.1, Chains of Domination launches June 29th (NA) and June 30th (EU).