To some extent, the debate over whether Heartsong or Power Torrent is better for holy priests is like comparing apples and oranges. It doesn’t change the fact that this is one of the most hotly debated topics in the priest community.
I have always stayed out of this discussion, because I felt like I didn’t have enough of an understanding of the issue to properly talk about it. However, with the impending loss of spirit that I’m facing by picking up Firelands gear and by breaking my T11 bonus, I have been dwelling on this topic a lot more. Since I know I’m not the only one thinking about this, I figured I would share my findings here and what I’m ultimately choosing to go along with.
In order to determine which enchant is a better choice for you, we need to first determine what it is that you are looking for or what you feel you need more of.
Heartsong has a chance to give you 200 spirit for 15 seconds when casting spells. Keep in mind that spirit is purely a regen stat. It does not give you any increases to your spell power or to your mana pool.
Power Torrent has a chance to give you 500 intellect for 12 seconds when casting spells. Intellect serves a number of purposes. Each point of intellect after the first 10 increases your mana pool by 15. It also increases your spell power, at a rate of 1 spell power per point of intellect.
Spirit and intellect both factor into the formulas for in combat and out of combat mana regen.
Base mana regen + % of spirit based regen from Meditation & Holy Concentration x 0.016275 x spirit x square root of the total amount of intellect
Priests have a base mana regen of 1029.5 every 5 seconds. Meditation gives you 50% of your spirit based regen while in combat. Holy Concentration increases this amount by an additional 30%. Currently, I have 2509 spirit and 5415 intellect. The square root of 5415 is 73.59.
1029.5 + 0.80 x 0.016725 x 2509 x 73.59
Next, we do our math from left to right, starting with the multiplication. The final numbers will always be rounded down, for the purpose of these calculations.
1029.5 + 0.01338 x 2509 x 73.59
1029.5 + 33.57042 x 73.59
1029.5 + 2470.4 = 3499
Out of Combat
Base mana regen + 0.016725 x spirit x square root of the total amount of intellect
1029.5 + 0.016725 x 2509 x 73.59
1029.5 + 41.963025 x 73.59
1029.5 + 3088.1 = 4117
These figures show what my regen would look like without any of the enchants mentioned above and without any party or raid buffs. Now let’s take a look at what my in combat regen would look like if I had a Heartsong or Power Torrent enchant on my weapon and the enchant procs. I’m choosing to go with in combat regen here because I don’t feel these enchants would have as much weight if you were standing still and not in combat.
In Combat (Heartsong)
1029.5 + 0.8 x 0.016725 x 2709 x 73.59
1029.5 + 0.01338 x 2709 x 73.59
1029.5 + 36.24642 x 73.59
1029.5 + 2667.4 = 3697
In Combat (Power Torrent)
1029.5 + 0.8 x 0.016725 x 2509 x 76.91
1029.5 + 0.01338 x 2509 x 76.91
1029.5 + 33.57042 x 76.91
1029.5 + 2581.9 = 3611
As you can see, the difference is quite miniscule. You are getting more regen from a 15 second Heartsong proc than you would from a 12 second Power Torrent proc, but not by much. The Power Torrent proc also temporarily increases your spell power by 500 and the size of your mana pool by 7500. So it could be argued which enchant you’re really getting more out of. Heartsong is great for regen, but only regen. Power Torrent may increase your regen by a smaller amount, but also buffs your character in other ways.
One way that you can close the gap between Power Torrent and Heartsong is by timing a Power Torrent proc with your Shadowfiend. Shadowfiend restores 3% of your total mana with each strike and usually strikes a target 10 times. If you have a larger mana pool, Shadowfiend will give you back more mana. This is one of the big reasons that Shadowfiend works so well with Hymn of Hope, which also temporarily increases the size of your mana pool. Let’s see how much mana Shadowfiend would return to you, using my unbuffed mana pool as an example.
103,122 mana x 3% = 3093 returned per swing
3093 x 10 swings from Shadowfiend = 30,930
Now, with the temporary boost to my mana pool from Power Torrent
103,122 + 7500 = 110,622
110,622 x 3% = 3318 returned per swing
3318 x 10 = 33,180
Power Torrent clearly came out ahead on that one. Keep in mind that this is only if you use your Shadowfiend when you have a active proc from Power Torrent. If you time it wrong, you won’t see the increased returns. This may require you to have Power Auras set up to indicate that you have the proc active and that it would be a good time to use your Shadowfiend. Feel free to use this export, from Rezznul over at the Red Noob Diaries.
Version:4.21; icon:Ability_Paladin_SacredCleansing; buffname:Power Torrent; x:80; texture:54; alpha:0.85; owntex:true; exact:true; size:0.19; randomcolor:true; y:-142; timer.a:0.85; timer.enabled:true; timer.Relative:BOTTOM; timer.x:-8
“So which one am I going to choose?”
For now, I’m going with Heartsong. I feel that Power Torrent is great, but it requires too many things to happen in order for it to be effective. Heartsong gives me consistent regen and I don’t have to rely on my Shadowfiend to make it shine. Shadowfiend has never been completely dependable and I don’t feel comfortable relying on that to make Power Torrent work for me. I realize that I am giving up a slight spell power boost and an increase to the size of my mana pool by not using Power Torrent, but I am prepared to get that intellect in other ways (i.e. trinkets and gems) if I have to.
At the end of the day, I would rather be the type of healer that has longevity in a fight instead of the healer that has a lot of throughput but can’t keep it up through a long encounter. Of course, these are just my opinions. Feel free to do what works for you and to try both of these wonderful enchants out and see which gives you more bang for your buck.
Many thanks to Hamlet from Elitist Jerks for being gracious enough to not only give me these formulas, but to help me understand all of this enough to where I felt confident in writing this post. Thank you!