Patch 7.2.5 only recently arrived for World of Warcraft, and already the next big update is available for players to check out on the Public Test Realm. Among other things, update 7.3 allows players to visit Argus, the homeworld of the Legion. Blizzard describes 7.3 as "a very story-driven update," with much of the new content being centered around the new Argus location. The version of 7.3 available on the PTR provides access to one of the three main areas that comprise Argus, as well as a limited number of story chapters.
There aren't many areas that can be treated as safe in Argus, but one is the Vindicaar, a "mobile base of operations" that will help you to get around. At least at this point, players can't fly in Argus, but they can make use of portals available on the Vindicaar. These essentially act as replacements for flight paths while sparing you the time it takes to actually reach your destination.
Improved casting animations are also included for Restoration Druids, Elemental and Restoration Shaman, Discipline and Holy Priests, and all Mage specializations. Blizzard is seeking feedback for all of these, and it notes that Shadow Priest will also receive updates in 7.3, but they aren't yet implemented on the PTR.
In addition to story content, you can expect Argus to eventually offer "areas with sandbox elements intended to be enjoyed even after you complete the main quest." These are compared to the Timeless Isle, Molten Front, and Isle of Thunder. The full, non-PTR version of 7.3 also will include the following, as laid out by Blizzard:
- Further chapters of the Argus storyline, including many cinematic story moments
- New World Quests
- Professions updates, including epic gems
- The Netherlight Crucible, which allows you to upgrade your Artifact to unlock a new way to customize your Relics
- New dungeon: Seat of the Triumvirate
- New raid: Antorus, the Burning Throne (though as with other Legion raids, it won't be released immediately with 7.3)
- Invasion Points, a new type of replayable content that let you fight the Legion on multiple different worlds
- Several other improvements and updates to existing features