Action Bar basics
The Action Bar is the left-most part of the Interface Bar at the bottom of the screen, and is used as a ready source for command shortcuts, abilities and spells. A player may drag and drop icons into the Action Bar in order to create a customized interface. Experienced players will give great attention to the layout of their Action Bar(s), as it represents the primary means of interface in combat, and is critical in allowing for quick action in an environment where 1-3 seconds delay can mean the difference between victory or a wipe.
- To the right of the command shortcuts are gold up ↑ and down ↓ arrows to switch to alternate Action Bars (see below).
When you learn a new rank of an ability or spell, all buttons on your currently active spec's action bars, which previously used the highest available rank, will be updated to use the new highest rank. As of Wrath of the Lich King, downrank abilities and spells are no longer available.
Changes in Battle for Azeroth
In Battle for Azeroth, the main Action Bar changes more than it ever has. It will now be centered at the bottom of the screen and be separated from the Bag slots and Micro Menu (which will now be pinned to the bottom right of the screen). The right side vertical Action Bar will remain the same.
Prior to Wrath of the Lich King
Buttons which used downranked versions of spells and abilities, and buttons on your inactive spec's skill bars were not updated. However, almost all different ability and spell ranks were removed with Wrath of the Lich King, so for the most part, keeping lower ranks around was no longer possible, anyway.
Additional Action Bars
The advanced interface options allows a player to add up to four other action bars (bottom left, bottom right, right 1, and right 2) to the screen. Doing so reduces the number of alternate Action Bars that are available via the up and down arrows situated to the right of the primary action bar. This means that a total of six Action Bars are available for the interface to handle regardless of the manner in which they are displayed.
A player may choose to have these Action Bars accessible via toggling of the gold arrows (the benefit being a screen with less clutter and better field of vision, an option sometimes chosen by melee classes), or may choose to have those bars displayed at all times (garnering the benefit of rapid access to a greater range of abilities and spells, an option typically chosen by casters).
There are 10 action bars, and they are allocated as follows:
|Action Bar||Used for|
|1||(Primary) Action Bar 1|
|2||(Primary) Action Bar 2|
|4||Right Bar 2|
|5||Bottom Right Bar|
|6||Bottom Left Bar|
|7||Druid Cat Form/Rogue Stealth/Warrior Battle Stance/Priest Shadowform/Monk Fierce Tiger|
|8||Warrior Defensive Stance/Rogue Shadow Dance/Monk Sturdy Ox|
|9||Druid Bear Form/Warrior Berserker Stance/Monk Wise Serpent|
|10||Druid Moonkin Form|
- Although most players quickly graduate to using Key Bindings for most of their frequently used abilities and spells, the action bar buttons will show Cooldown info (usually with a shadowed animated-pie-chart-like display) which makes the action bar still a useful UI element.