World of Warcraft Battle for Azeroth
Changes to gameplay A "stat squish" and "item squish" was implemented to lower the numbers used in the game, e.g. a legendary item previously with a level of 1000 reduced to 265. Unique class-specific buffs are added back, i.e. mages' Arcane Brilliance and priests' Mark of Fortitude. Titanforging—a random event that raises the initial item level of an item gained via drops or rewards—is still in the game; however, if the item is one of those affected by the Heart of Azeroth, then that item cannot be titanforged.
Changes were also made to levelling in earlier content with Legion's 7.3.5 patch. The level-scaling tech introduced in Legion will not only be continued in the new continents of Kul Tiras and Zandalar, but will also be applied to content from prior expansions, allowing larger level brackets for lower level zones. Further, as previous expansions are now included in the base game, the level ranges for those expansions are now broadened, allowing players to spend more time leveling in preferred expansions and avoid others entirely. Some examples include a zone like Westfall having its level bracket (at 10–15 as of Legion) increased to 10–60, whilst continents such as Outland and Northrend will now share a 60–80 level bracket. The aim of this change is to encourage more player choice whilst levelling and to allow players to experience the full story of a particular zone without overlevelling the relevant quests.
There were not as many class changes in Battle for Azeroth as there were for Legion, although Ion Hazzikostas noted, "Not all experiments were successful (i.e. Demonology Warlocks). Survival Hunter execution needs work but we're committed to the melee Hunter.
Heart of Azeroth The Heart of Azeroth is an artifact given to the player character from the world soul via Magni Bronzebeard. It is a necklace that can use the power of Azerite, the lifeblood of the embryonic titan Azeroth (See Plot, below). Azerite is similar in function to Legion's artifact power, in that it is gathered normally from playing the game and is used to upgrade an artifact; likewise, the Heart is similar in function to Legion's artifact weapons by having the capacity to be constantly upgraded. Unlike artifact weapons, however, the Heart is shared with all of the player's specializations and can empower all eligible pieces worn simultaneously.
Valid pieces for Azerite empowerment are available for the chest, shoulder, and head slots of all classes. This equipment has multiple tiers of that can be unlocked, represented by a series of concentric wheels with icons representing individual powers; as individual powers are selected, they rotate into slots at the top of the interface, activating the selected benefit and locking out the others unless the player pays to reset their decision. Outer rings offer multiple choices, some based around the character's class and specification, others around the zone or circumstances in which the gear was acquired. The innermost circle offers no such options, instead being a boost to the level of the item itself, and thus providing a flat all-around benefit.
Azerite equipment is currently balanced around being able to unlock the outermost, earliest tier of power immediately upon acquisition, while delaying further advancement until the Heart has been further empowered. For example, the first piece of Azerite equipment, gained shortly after the Heart itself, is fully empowered once the Heart of Azeroth has reached level 3. A character at 120 (the maximum for the expansion) may find a piece whose first tier requires the Heart to have grown to level 12 or greater.
Allied races The allied races, who were formerly neutral factions or newly introduced, can be recruited by completing quest chains. Four of these races were unlocked when the expansion became available for preorder in January 2018, and four more will be added after the game's launch.
The Alliance will be able to unlock the void elves (exiled blood elves who can tap into shadow magic, trained by Alleria Windrunner after her experiences on Argus), Lightforged draenei (draenei members of the Army of the Light who fought the Legion on Argus), Dark Iron dwarves (fire-blooded cousins of the in-game dwarves of Ironforge), and Kul Tiran humans (larger, more heavyset versions of the in-game humans of Stormwind).
The Horde has access to the Nightborne (former night elves from Suramar), the Highmountain tauren (moose-antlered cousins of the in-game tauren of Mulgore), the Mag'har orcs (survivors of the Iron Horde from Warlords of Draenor), and the Zandalari (progenitors of all of the trolls of Azeroth).
When an allied race has been unlocked for a player, new characters from that race will start at level 20. If a player levels an Allied race from 20 to level 110 without using character boosts, they will be rewarded with a unique "Heritage Armor" for transmogrification that reflects the unique lore behind the race but is limited for use to that race. Doing the quests to unlock the allied races will also unlock the races' unique mounts for use by the characters of their faction. The void elves, Lightforged draenei, Highmountain tauren, and Nightborne, as races tied to the storyline for Legion, were made available with the preorder on January 30, 2018. The Dark Iron dwarves and the Mag'har orcs are made available upon completing the "War Campaign" in Kul Tiras and Zandalar and reaching Exalted with one faction's War Campaign reputation; the Kul Tiran humans and Zandalari will be made available later in the expansion. Game director Ion Hazzikostas also indicated that additional Allied Races may be available in the future.
Warfronts Warfronts will be a new form of 20 player PvE content. They will function similarly to battlegrounds but with more focus on base building, capture and control of territory and resource control to focus on Warcraft's RTS roots. The warfronts will not always be active on a regular basis since there will be a build up to each one.
Island expeditions Similar to the 3-player scenarios in Mists of Pandaria, island expeditions are a new form of 3-player content that will provide dynamic challenges that involve battling against a group of either advanced AI NPCs or players in order to gather Azerite for their faction's war effort.
PvP ruleset The expansion brings a major change to the PvP ruleset on each realm. Every realm by default only allows players to attack NPCs in the open world; players who wish to engage in world PvP now have a setting called "War Mode" that can only be toggled on or off in their faction's capital city (i.e. Stormwind for the Alliance and Orgrimmar for the Horde). While in War Mode, players have access to new talents and abilities, as well as a slightly accelerated rate of XP gain. Characters with War Mode activated are only able to see other players with War Mode, unless in their own capital cities.
Players who engage in War Mode and are successful at killing multiple enemy PC's without dying in exchange receive an "Assassin" buff that increases their damage and healing. Eventually, such a character gains a bounty on their head, giving other players a reward for killing them.
Roleplaying (RP) servers do not behave the same way as the regular servers. The game director said, "The default behavior for RP servers in Battle for Azeroth will be that PvP flagging people would see other flagged players on that same server. We don't want to split up RP communities.
A new battleground called Seething Shore was previewed in Legion's patch 7.3.5. It is located in Silithus and set after the events of the Antorus raid; it involves players battling to take control of Azerite resources in randomized locations. It was the first battleground added to the game since 2012's Mists of Pandaria.