View various attributes of spellpower, mana, and ranks for Priest Flash Heal spells
In the game of 21 players draw randomly sorted cards until the sum of their cards equals 21, or have the highest sum among the players without going over. Healers face an interesting problem: Like the game of 21 they must be able to heal a damaged player as close to full as possible without (significant) overhealing. This game occurs literally thousands of times over the course of a single raid, where overhealing may cause the healer to run out of mana (its primary resource) when the raid needs it most. Raid healers have an added difficulty in that they have to coordinate with each other to reduce overhealing; it would be like playing 21 together and some penalty is incurred by the team if anyone on the team goes over.
Significant overhealing is inefficient and reduces the healer's endurance during a fight, increases raid downtime to drink, and may impose real cost in the need to purchase more consumables (both on the part of the healer as well as those being - or would be - healed).
In the course of this exercise we will explore the most mana efficient spells by looking at the spell rank, spellpower and its coefficient, and its mana cost.
A Priest's Flash Heal Rank 7 spell heals an average of 901 hitpoints at a cost of 380 mana, a ratio of 2.37 hitpoints per mana. The higher the ratio the more mana efficient the spell.
Figure 1
The graph above demonstrates the mana efficiency of each rank of Flash Heal. Interestingly, higher ranked base spells are increasingly more efficient to use, but cost more mana. As long as there is sufficient mana and assuming there is no penalty for overhealing, casting with the highest ranked spell is the most efficient.
- If the emphasis is healing amount, higher ranks are better
- If the emphasis is mana conservation, especially in longer fights or where damage is relatively light, lower ranks are better
While these points are obvious, a game of 21 can't be won by playing only the lowest, or the highest, cards. Some combination or compromise is required to ensure the sum doesn't go over 21.
Spellpower has a powerful impact on healing as it is essentially an additive, free effect on top of the base heal. The spellpower coefficient is calculated as: spellpower / 3.5 * 1.5; if the spellpower is 500 then the effective spell coefficient is ~214 added healing, bringing the power of Flash Heal Rank 7 to 1,115 at the same mana cost as the base spell. It's mana to health, or efficiency, ratio increases from 2.37 to 2.93.
Base formula
( ( Spellpower / 3.5 * 1.5 ) + Base spell effect ) / Mana = Mana to Heal Ratio
Base Spell without Spellpower
( ( 0 / 3.5 * 1.5 ) + 901 / 380 = 2.37
Base Spell with 500 Spellpower
( ( 500 / 3.5 * 1.5 ) + 901 / 380 = 2.93
This chart (below) shows the benefits of spellpower to healing for each rank of spell.
Figure 2
While spellpower increases the overall healing as well as the mana to healing ratio, it can create scenarios for overhealing. Consider the following example:
A damage-over-time spell is applied to a player at a rate of 500 damage per one and a half seconds for 2 minutes. A Priest with 900 spellpower may choose to cast one of three ranks:
- Rank 1 for ~280 healing at 125 mana
- Results in no overhealing and one dead player
- Rank 4 for ~840 healing at 215 mana
- Results in overhealing at a cost of 86 mana
- Rank 7 for ~1300+ healing at 380 mana
- Results in overhealing at a cost of 232 mana
If Flash Heal is cast 80 times over the course of the 2 minutes, this will result in 6,915 and 18,597 mana used in overhealing for Rank 4 and Rank 7, respectively. That mana equates to 27,016 and 62,936 health.
Example: Mana Cost for Overheal with Rank 7
( ( ( spellpower / 3.5 * 1.5 + base damage ) as sp - damage over time tick amount / sp * mana cost * time of fight / cast time ) )
(( ( 900 / 3.5 * 1.5 ) + 901) as sp - 500 / sp * 380 * 120 / 1.5
Disclaimer: This section may be misintrepeted to mean lower ranked spells are more efficient than higher ranked spells. This is not true in itself. However, lower ranked spells become more efficient when coupled with increased spellpower.
Figure 3
This graph shows an interesting phenomenon that feels counterintuitive. Lower ranked spells respond more to increased spellpower, or rather spellpower has more impact on lower ranked spells. Here are some observations:
- Lower ranked spells cost less mana in absolute terms. Therefore, they have more to gain from increased spellpower.
- Lower ranked spells are significantly less efficient than higher ranks, but adding spellpower actually increases their efficiency more quickly than higher ranks.
- This view of the data proves that downranking can be a viable, efficient strategy so long as there is enough increased spellpower.
Note that the distance between ranks close as the rank becomes higher. This suggests an interesting detail observed in the subsequent section.
Figure 4
While the previous section showed that spellpower has a greater effect on lower ranked spells, the above graph shows that absolute healing at higher ranks increases more quickly with less mana efficiency.
Healers have powerful tools to keep the raid alive and moving, and spellpower has a multiplicative impact on that toolkit.
- Do nothing. It's possible overhealing isn't a significant issue for you or your healers.
- Assign the best geared healers to those who consistently take high damage and assign others to general raid healing. This may be especially handy if there is a lot of gear-tier diversity among the priests.
- Ask all healers to simply target a single or multiple heal amount, and allow them to choose the appropriate spell and rank for that assignment based on their current spellpower. For example, a class leader could advise all healers to target ranks with an effective heal for 500, 800, and 1200 hitpoints.
- A well-geared priest could target 800 hitpoints by using Flash Heal rank 3, while a lesser geared priest may have to use rank 6 or rank 7.
- Note: the purpose of this is to encourage healers to think in "tiers" of spells and move away from the "one spell fits all" approach.
- Create an Innervate priority list for Druids so they know who to focus on to get the best, or most immediate, return.
- An interesting point: it seems obvious Druids should target the best geared priests for Innervate. However, it may be equally or more important to target priests who run out of mana first (and presumably are not the best geared) so that the overall absolute healing is still high.