At low levels, this is usually the warlock's fastest option for dealing damage to groups of mobs. Be aware however that this will generate a large amount of threat.
Very situational, for it pulls threat and costs Soul Shards. Mainly useful in instances for AoE.
This is a very powerful spell that combines the natures of flame and water. It calls forth the essence of fire and delivers it through massive thunderheads of vapor and brimstone, creating an actual firestorm. This spell is very destructive, and will cause damage to any foes and buildings in its sphere of influence. Use this spell with care, for the rain of fire knows no friends.[2]
Rain of Destruction is one of Gul'dan's Heroic Abilities in Heroes of the Storm. It differs from Rain of Fire in that it summons green fel meteors, each dealing a separate amount of damage.
Patches and hotfixes
Patch 7.2.5(2017-06-13): Rain of Fire's damage increased by 25%.
Hotfix (2016-09-26): "Fixed a bug that prevented Rain of Fire from always doing all 8 ticks of damage on PvE and PvP targets."
Hotfix (2016-09-23): "Rain of Fire damage increased by 11%, and cast time removed."
Hotfix (2016-08-04): "Rain of Fire will continue to deal damage if the Warlock is silenced, feared, or stunned."
Hotfix (2016-08-01): "Rain of Fire should no longer close your loot window when it does damage."
Patch 7.0.3(2016-07-19): Now costs Soul Shards and is no longer channeled. Damage increased by 100%.
Hotfix (2014-12-15): "Rain of Fire's damage has been reduced by 60% and no longer generates Burning Embers."
No longer causes a stun after hitting a target three times.
No longer requires Immolate to be present to generate Burning Embers.
Rain of Fire's damage over time will now hit every 1 second, down from 2 seconds. The damage animation for the damage over time effect will no longer always display.
Patch 5.0.4(2012-08-28): Now an Affliction and Destruction specialization ability. Duration reduced from 8 to 6 sec.
Patch 4.1.0(2011-04-26): Damage has been increased by 25%.
Patch 4.0.3a(2010-11-23): Damage has been increased to be more comparable to other area-of-effect abilities.
Patch 1.1.0(2004-11-07): Duration, mana cost, and damage slightly reduced, deals its damage in more frequent intervals.