Eclipse Bar

For the retail ability, see [Eclipse].

Eclipse Bar on a Balance druid's player frame prior to patch 6.0.2.

Solar Eclipse

Lunar Eclipse

The Eclipse Bar is a resource mechanic for druids specializing in Balance. It shows the progress the druid has made towards reaching Eclipse, as well as the type of energy the Druid is currently able to gain.

The bar extends 100 units in both directions; when the pointer reaches the left edge, Lunar Eclipse is triggered, while reaching the right edge triggers Solar Eclipse.

Eclipse Bar Mechanics

Cataclysm Classic

The Eclipse Bar is primarily affected by three spells: [Starfire] (Solar Energy), [Wrath] (Lunar Energy), and [Starsurge] (either Solar or Lunar). The [Euphoria] talent gives these spells a chance to double their Energy generation. Whenever one type of energy reaches 100, it will cause an Eclipse:

•  Eclipse (Solar) increases Nature damage by 25% until Solar Energy is reduced to 0.
•  Eclipse (Lunar) increases Arcane damage by 25% until Lunar Energy is reduced to 0.

Initially, the bar will move in either direction whenever a spell is cast. Once an Eclipse has been triggered, it will only move back towards 0, at which point it will be locked into moving towards the other Eclipse. The Eclipse Bar will reset on death, disconnection, or when changing instances. Changing glyphs or talents will cause the Eclipse Bar to unlock without resetting back to 0.

Mists of Pandaria

• [Astral Communion] generates 25 Energy per second for 4 seconds. Like Starsurge, it always generates the type of Energy that's most beneficial.
• Using [Celestial Alignment] resets the Eclipse Bar to 0, but does not unlock its direction. No Lunar or Solar Energy can be generated while Celestial Alignment is active.
• During a Lunar Eclipse, [Hurricane] changes into [Astral Storm].

Warlords of Draenor

In Warlords of Draenor, the Eclipse Bar cycles on a timer, gradually increasing the damage of Nature and Arcane spells based on its progress in either direction.

Patch changes

• Patch 7.0.3 (2016-07-19): Removed.
  
• Hotfix (2014-11-15): Resolved an issue where the balance cycle may incorrectly force the Druid to stand up.
  
• Hotfix (2014-11-13): Resolved an issue where the Eclipse indicator in the UI can sometimes not match the Druid's current Balance power.
  
• Patch 6.0.2 (2014-10-14): Redesigned. Lunar and Solar Energy now cycle on a timer rather than from spell casts, increasing the damage of your Lunar and Solar spells by up to 30% based on the progress of the Eclipse Bar.

  Previous effect: Your [Wrath] now generates Lunar Energy and your [Starfire] now generates Solar Energy. When you reach 100 Solar Energy you will trigger a Solar Eclipse, increasing all Nature damage by 15%. When you reach 100 Lunar Energy you will trigger a Lunar Eclipse, increasing all Arcane damage by 15%, transforming your [Hurricane] spell into [Astral Storm]. When triggered, both Lunar and Solar Eclipse grant 15% spell haste for 15 sec and energize you for 50% of your maximum mana.
  

• Patch 5.4.0 (2013-09-10): Now energizes the Druid for 50% of their maximum mana when triggered, up from 35%.
  
• Hotfix (2012-10-01): Starsurge casts that trigger an Eclipse now deal the correct amount of damage.
  
• Hotfix (2012-09-14): Eclipse should no longer provide bonus damage after it fades.
  
• Patch 5.0.4 (2012-08-28): Lunar Eclipse now additionally converts [Hurricane] into [Astral Storm]. Both buffs now also grant 15% spell haste for 15 seconds and restore 35% of maximum mana.
  
• Patch 4.1.0 (2011-04-26): The direction of the Eclipse bar now resets after the druid dies and resurrects.
  
• Patch 4.0.1a (2010-10-26): The pointer on the Eclipse Bar indicates where it goes to after the next Starsurge.
  
• Patch 4.0.1 (2010-10-12): Converted from a talent into a Balance druid resource mechanic and given a dedicated UI bar.