Spell power

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"Spell Power" redirects here. For the former Mage talent, see [Spell Power].

Spell power is an attribute that increases the effect of spells. Spell power increases the damage amount of damaging spells and the healing amount of healing spells.

Prior to Patch 3.0.2, the attribute known as spell damage would only increase the effects of damaging spells. Healing spells were only increased by the healing attribute. As of Patch 3.0.2, spell power now affects both types of spells. Nevertheless, there are items which can increase your bonus healing independently of damage spells. Similarly, there are items which grant bonuses only to certain magic schools such as fire or nature.

As of Patch 4.0.1 the ability to downrank has been removed. As well, spell power has been removed from Wrath of the Lich King gear (except weapons and trinkets) and gems, but casters now gain 1 spell power per point of intellect. Spell power on gems was changed to intellect; for example, +23 spell power became +20 intellect.

Information about spell power can be found on the Character tab of the Character info window under the Spell heading. The Bonus Damage attribute represents your spell power's contribution to general spell damage. Hovering your mouse over this attribute will show you the specific bonus damage for individual schools of damaging magic. These are typically equal to or greater than the base Bonus Damage attribute. The Bonus Healing attribute represents your spell power's contribution to healing spells. As with damage schools, this attribute is typically equal to or greater than your general Bonus Damage attribute.

Players often refer to this attribute as simply +damage, +dmg, or plus damage. For effects that target a specific school, it is similarly referred to by that school such as +fire. In particular, healers commonly refer to items with only a healing bonus as +healing.

Your bonus damage and bonus healing from spell power do not usually apply directly to a spell. Each spell (or each component of each spell) which causes damage or healing has a spell power coefficient which determines how much of your bonus damage or bonus healing will be applied to the spell. The coefficient may be more or less than 100%, depending on various spell factors. Rules for calculating the coefficient are discussed in the sections that follow.

Sources of spell power

Spell power is found primarily on equippable items, but can also be increased with potions, buffs and some class talents. Items with the following item suffixes will add spell damage or healing:

Item Suffix Effect Note
... of Arcane Wrath + Arcane damage
... of Fiery Wrath + Fire damage
... of Frozen Wrath + Frost damage
... of Healing + Spell power (was only healing spells)
... of Nature's Wrath + Nature damage
... of Shadow Wrath + Shadow damage
... of Sorcery + Spell damage (not healing)[citation needed]
+ Stamina
+ Intellect
Found only on "Abyssal" items on summoned Silithus bosses.
... of the Crusade + Spell damage and healing
+ Defense rating
+ Intellect
Introduced in The Burning Crusade
... of the Hierophant + Healing
+ Stamina
+ Spirit
Introduced in The Burning Crusade
... of the Invoker + Spell damage and healing
+ Spell critical strike rating
+ Intellect
Introduced in The Burning Crusade
... of the Nightmare + Shadow damage
+ Stamina
+ Intellect
Introduced in The Burning Crusade
... of the Physician + Healing
+ Stamina
+ Intellect
Introduced in The Burning Crusade
... of the Prophet + Healing
+ Spirit
+ Intellect
Introduced in The Burning Crusade
... of the Sorcerer + Spell damage and healing
+ Stamina
+ Intellect
Introduced in The Burning Crusade

All spell damage and healing gains stack. The total bonus is determined by adding individual bonuses from all equipped items, all buffs, and any talents. The total amount of spell damage and healing can be tracked on the character sheet, under the Spell tab. Bonus Damage shows the total amount that applies to all schools. Mousing over Bonus Damage will break down the benefit by magical school, which includes items that only affect one school. Bonus Healing shows the amount that will be applied to healing spells.

Spell coefficients

How much spell power contributes to the effect of a spell varies from spell to spell. It is generally related to the base damage or healing of the spell. The portion of your spell power which is contributed to a particular spell is referred to as the spell power coefficient. As spell power increases, the amount healed by the spell increases:


Greater Healing Wave.png

A Level 85 Shaman's Greater Healing Wave heal amount increases with Spell Power

The spell power coefficient typically varies with the spell's base amount. In general, spells with higher base damage or healing have higher spell power coefficients. The intention is for the coefficient to scale with the overall power of the spell being cast. That is, a spell which heals for 100 should receive less benefit than a spell which heals for 1000. If they received the same benefit, it would be far more efficient to "spam" small spells to get the same amount of free bonus damage/healing as you would get for casting the larger spell. Scaling the spell power coefficient helps preserve the base mana efficiency of spells.

Level 85 Shaman Healing Spells.PNG

That said, the correlation between base damage and the strength of a spell is not perfect. The addition of spell power effects may change the mana efficiency of a spell significantly. When ordering the mana efficiency of your damage and healing spells, you should consider the effects of spell power, as this may change their ranking compared to if you used only the base states of your spells.

The Base Damage and Base Healing amounts vary by spell, and increase with level. But the spell power coefficients remain constant for a given spell for different player levels.

Level 85 Shaman

Level 85 Shaman Healing Spell Power Coefficients, and Base Heal amounts
Spell Base Heal Amount Spell Power Coefficient
Greater Healing Wave 9606 1.281218
Riptide (HoT portion) 7826 1.042315
Healing Surge 4803 0.640061
Chain Heal 3516 0.463787
Healing Wave 3002 0.400190
Riptide 2364 0.315426
Unleash Life 1996 0.266558
Healing Rain 755 0.124924

A spell's tooltip will already include the effects of your Spell Power, and any other buffs.

Using the example of [Greater Healing Wave] of a level 85 Restoration Shaman with 4,242 Spell Power:

  • base amount healed by [Greater Healing Wave]: 9,606
  • Add 25% healing bonus from [Purification]: 9606 * 1.25 = 12,008
  • Assume additional 6% bonus from Spark of Life: 12008 * 1.06 = 12,729
  • Add 5,435 contribution from Spell Power: 12,728 + (4242 * 1.281218) = 18,164

Which matches what the in-game tooltip reports: "Heals a friendly target for 18164."

Rules for applying spell damage and healing

  1. Calculate spell time using the base spell cast time before talents and gear. (The in-game tool tip will include those bonuses; refer to Wowpedia's spells section for base cast times for all spells.)
  2. Spells that take longer than 7.0 seconds to cast are treated as if their casting time was 7.0 seconds, and spells faster than 1.5 sec are treated as if their casting time was 1.5 seconds.
  3. Damage benefits are applied before any talents or buffs that may otherwise increase your spell damage.

Penalty rules

Spells learned before level 20

Many spells have multiple ranks. To avoid abuse of lower ranks to have a similar effect at a negligible mana cost, any spell learned below level 20 receives a large penalty. If such a spell has a shorter cast time than a higher rank, this is also taken in to account. This penalty can be calculated by subtracting 3.75% for each level lower than 20.

(20 - Level Spell is Learned) * .0375 = Penalty

Downranked spells

The ability to downrank has been removed with the release of patch 4.0.1

Main article: Downranking

Downranking, the act of purposefuly using a lower-rank cheaper spell, no longer has any mana benefit as of Patch 3.0.

Spells with additional effects

Spells with additional effects, like a slowing effect, receive a penalty for each effect. Typically the penalty is 5% per additional effect, but can vary according to the developers' whims. For instance, here is the calculation for Rank 7 (L80) of [Insect Swarm] (Druid), which is an over time spell with a chance-to-hit debuff:

C = (12.0 / 15.0) * 0.95
  = 76.00%

Examples of these spells include: [Blast Wave] (Mage), [Blizzard] (Mage), [Insect Swarm] (Druid)

Spells that both damage and heal

Some spells, namely Life Drains, both damage the target and heal the caster. The bonus is split between the healing and damaging portion, roughly in proportion to the amount of healing and damage involved. That is, if a spell heals 4 points for every 1 point of damage, 1/5 of the spell's bonus will go to damage and roughly 4/5 will go to healing. Because bonus healing does not apply to these spells, the 1.88 multiplier is not used for the healing portion.

Thus Drain Life's bonus is applied 50%/50% to damage/healing, while Devouring Plague's bonus is split roughly 75%/25%. The exact equations are unknown at this time, but a reasonably close answer can be obtained by:

CDamage = CTotal / (Damage Amount / [Damage Amount + Healing Amount])
CHealing = CTotal / (Healing Amount / [Damage Amount + Healing Amount])

Examples of these spells include: [Devouring Plague] (Priest), [Holy Nova] (Priest), [Drain Life] (Warlock)

Exceptions

  • Corruption (93%), Curse of Agony (120%), Curse of Doom (200%) and [Shadow Word: Pain] (110%) receive a reduced bonus.
  • [Drain Soul] has its bonus reduced to half (214%).
  • [Fireball] has a small damage over time component, but is not considered a hybrid spell, so it receives only the Direct Damage bonus to its direct damage component. Spell damage gear never increases the DoT on fireball.
  • [Holy Fire] does not follow hybrid spell rules.
  • [Mind Flay] does not follow channeling rules and uses 57% damage applied.
  • [Soul Fire] is capped at 115%.
  • [Pyroblast] deals 115% of +spell damage on impact and 20% of +spell damage to its DoT component.

Additional notes

  1. +Healing does not apply to bandages or potions. Trinkets should no longer be affected.
  2. Shaman totems receive benefit from +Damage.
  3. Hunter Traps don't receive a benefit from increased spell damage.

Patch changes

  • WotLK Patch 3.0.2 (2008-10-14): All items and effects which grant bonuses to spell damage and spell healing are being consolidated into a single stat, Spell Power. This stat will appear with the same values found on items which grant "increased spell damage and healing" such as on typical Mage and Warlock itemization.
    • For classes which do not heal, they should see no change in the character sheet other than new tooltip wording.
  • Healing characters will see their bonus healing numbers on the character sheet decrease, however, all healing spells have been modified to receive more benefit from Spell Power than they received from bonus healing, with a net effect of no change to the amount healed by their spells. Some talents have had to be rebalanced to accommodate this change, but the amount healed will remain roughly the same. In addition, some talents will provide only healing spell power.

See also