Greetings,

Over the past months I have seen many questions about our regen model return:
- the value of spirit
- what is mp5 and how much is it worth?
- more intellect or more spirit?

Once upon a time, it was possible to make a simple answer to all of these questions. Unfortunately, this is no longer the case. Our regen model has become vastly more complex. The mathematical analysis becomes hard for many players and there is an accurate answer that will always prove true. I have the impression that people lost their intuition in understanding how regen works. I will attempt to wake the intuition of players without throwing math books at them.

The regen of intellect and spirit

Our first and most dominant source of regeneration is our "intellect and spirit" regeneration, often nicknamed spirit regen. This regen is a "product" of intellect and spirit. It is important to know this, as it defines the scaling behavior of our mana regen.

This product looks something like: A * Spirit * sqrt(Intellect) where A is small and irrelevant for this discussion. What matters is the product of spirit and the the squareroot of intellect. They work in tandem and spirit is its strongest contributer. This does not mean that spirit is always better! To get the best result we still need to invest points in intellect, only less. Just check:
- 200 spirit * sqrt( 100 intellect) = 2000
We add 100 points, and try different gearing methods:
- 200 spirit * sqrt( 200 intellect) = 2829
- 300 spirit * sqrt( 100 intellect) = 3000
- 266 spirit * sqrt( 133 intellect) = 3068
(the results are not ingame results)

Adding points to spirit proves better than adding points to intellect. But we also see that adding points to both is the best method. In fact, to maximize 'spirit' regen on your character sheet, having twice as much spirit as intellect will give the best results.

The scaling of our regen

When we added 66 points to spirit and 33 to intellect (99 total), we gained 1068 points of regen in our example. Let's add another 99 points:
- 266 spirit * sqrt( 133 intellect) = 3068
- 332 spirit * sqrt( 166 intellect) = 4278
(the results are not ingame results)

This time we gained 1210 points. So, our model scales: the more intellect and spirit we have, the more valuable they become. With the current patch, 3.2, we can expect their individual value to beat mp5 at ulduar gear levels in regen alone.

Raid buffs and spirit regen

Raid buffs that add intellect, and thus they do not only add their direct value but also increase the value of all the spirit that you already have. Likewise, raid buffs that add spirit increase the value of all the intellect that you have.
Raid buffs that give both spirit and intellect, such as blessing of kings and Fel intellect, will boost your regen quite a lot. For example,

Blessing of Kings will not just add '10%' to your regen from intellect and spirit:

(spirit * 110%) * (sqrt(intellect * 110%)) = spirit*sqrt(intellect) * 115.4%
We have a 15.4% increase of our 'spirit' regen.

Manabar regeneration

WotLK (or 3.0) introduced a lot of new ways to regen a piece or % of your manabar:
- Replenishment
- Shadowfiend
- Mana totem
- Hymn of Hope
- Rapture

These depend on the size of your manabar, which is defined by intellect. So, the more intellect we have, the more regeneration we get from these abilities. This does not depend on mp5 nor spirit!

MP5 remains static

How does MP5 work in the game? Adding a point to mp5 will increase your regen by 1 point. Adding another point to MP5, just adds another point. No matter how many points you have in intellect, spirit or MP5, you only get 1 point of regen per mp5.

This is reliable but also restricted.

Gearing strategies

How should a player translate these three separate sources of regen into a single gearing strategy? Depending on the situation one source of regen may prove more favorable than the other. Here's a breakdown of a few gearing strategies, their pro's and con's:

- Stacking Spirit: Spirit increases your own manaregen nicely. This method also requires some intellect, but typically enough intellect is provided on spirit gear. It is good for solo, good for 5-man, very good for 10man, very good for 25 man. It is acceptable for PvP, but sub optimal. It is reliable and increases in strength with buffs. But despite these benefits, it still underperforms compared to MP5. For holy priests, spirit can beat mp5 thanks to the SP bonus it provides but it requires a healthy amount of gear (think T8) to make spirit worth the stat investment.

- Stacking Intellect: Stacking intellect increases the regeneration from external factors: shadowfiend, totems, replennishment. They can yield a great amount of manaregen, but depend on group setup. Expect big jumps in performance depending on the group. It is not so good for solo, unreliable for 5-man, very good for 10 man if it is min maxed, excellent for most 25 man. If you stack enough intellect (more than 1200), spirit becomes a worthy companion for holy priests but less so for Disc priests. It can even work well after a combat ress. Highly recommended for Disc priests.

- Stacking mp5: mp5 never yields tremendous numbers, but gives a solid mana regen regardless of the situation you're in. It is good for solo, excellent for 5-man and PvP, good for 10man, good for 25man. It is especially fit for blue geared raiders, or raiders still early in Naxx levels. Gradually, intellect (and spirit for holy priests) will outweigh mp5 once the raider starts progressing in Ulduar. Still, up to 3.2 available gear, MP5 remains a strong regen stat.

- Balancing Spirit and Intellect: Balancing intellect and spirit to a given ratio is about maximizing spirit regen and manabar regen without sacrificing either. Under most raid circumstances this will yield the best regen. Under extreme conditions, it may prove slightly sub optimal but the loss of regen is typically small. Leaning towards more intellect emphasizes synergy with the raid. Leaning towards more spirit is more flexible towards raid setup. Yet the 'neutral' point between a healthy raid synergy and spirit regen lies at about 1300 spirit and 1500 intellect raidbuffed. For lower stat levels: intellect always needs to be a bit higher. This neutral point is not a 'canon' though and one can easily shift the balance up to 200 points before feeling a pinch! This method is acceptable for solo, acceptable for 5-mans but excellent for 10m and 25m. This will probably perform best overall for Ulduar raiders. It may be noted that using this strategy at low gear levels is not the most effective method but it's a good thing to upgrade to as soon as the player has full epic gear.

- Stacking intellect and mp5: This strategy is excellent for lower geared raiders. The mp5 gives them a good basis and the intellect lets them scale with the party. This method may even provide the best raw regen, but a more spirit based approach is preferable at high end gear. It is excellent for solo and 5-mans. It is the best for 10m and 25m Naxx but becomes less optimal as the player starts reaching Ulduar gear levels.

(stuck)

Wow-ee, that's quite a post. Thanks for doing all the math! That stuff escapes my understanding sometimes.

Zusterke, thank you for running the numbers here. Do you have any information on crit versus haste (since these two seem to be the most common "complementary" stats for us) in 3.1?

I do not have numbers on them regarding throughput. In terms of their regen value, crit will give more holy concentration uptime than haste. I was still working in spreadsheets and notes when I found this post at EJ's with a proof for that:
http://elitistjerks.com/f77/t47907-3_1_ ... ost1127573
But it may be a bit hard on the math side so let me quote just this:


I'm convinced haste is still desirable to some degree though, but more as a throughput stat.

EDIT: let me add that both crit and haste have a 'diminishing' return in terms of HC uptime. But the point where haste > crit is probably out of realistic gearing strategies according to early estimates. I can only base myself on other lecture though. I did not work this out myself in detail and thus I'm not 100% convinced.

What's the amount of mana, would lowering the priority of regen/ MP5 for a priest?

Rephasing:

If you have Unlimited Mana pool. I would assume mana regen is no longer useful for that priest.

So for reality if you have 20K mana. regen / mp5 should be in lower priority gear- wise? For fight under 10mins or Shadowfend can only be casted 1 time.

I'm sorry Dubbc, but I'm not sure I understand your question. I assume you ask at what amount of mana regen, does the value of regen diminish. The answer depends on the player, entirely. I see people run with a notable lower regen than myself, like 460mp5, and claim that this is enough. I run with 560mp5 raidbuffed, while casting, and I can get it up to ~600 if needed. I spamheal a lot, and like to take short mana breaks where I blow all cooldowns that save mana so I can rebuild my manabar as much as possible in a nick of time. So, for me, the extra regeneration power is welcome. But some healers are content with merely 400-450 mp5 while casting.

I thought he was asking "How much starting mana do you have to have to ignore/downplay regen because you have enough mana at the beginning to do the whole fight."

MP5 and Spirit are changing next patch...from what I understand Spirit will be reduced by 40% and MP5 will be getting buffed to compensate. Druids are the reason for the change... but the thing that gets me is Priests are considered the Main Healing class but other classes have fun and unique healing properties...why dont we have a Combat Res? Why dont we have that huge mana reg buff? Right now in the Naxx runs I am running 3rd in the Recount healing stats and i am decently geared... and I am healing like crazy.. I hope the changes in the next patch help us regen faster.

No. The value of MP5 remains exactly the same.
Spirit/Intellect regen is reduced by 40% but your regen while casting from Spirit/Intellect is increased from 30% to 50% (66% increase) so your net regen from spirit while casting remains the same. If you spend 100% of your time inside the five second rule, you will not see any difference. If you spend 95% inside the five second rule, then your 5% outside the five second rule is reduced by 40% which results in 95%*60%*50%+5%*60% = 31,5%. Before the patch, this was: 95%*30% + 5% = 33,5%... or only a 6% regen nerf on spirit/intellect alone.

So, both intellect and spirit reduce in regen value, however... a large part of the regen acquired from intellect comes from Replenishment (which remains the same) and the Shadowfiend (which is being buffed). This effective makes:
- intellect climb a little in value
- spirit lower a little in value
- mp5 remain the same

It would almost seem that intellect is now the better stat but this is only partially true. For reasons explained above, the value of spirit increases for every point of intellect you have. Despite the change, after a while you will have stacked enough intellect to make spirit the best choice of regen stat. The exact ratio between these 2 varies with your gear, and theorycrafters have not exactly streamlined their conclusions yet. Grearing for int and spirit will probably still beat gearing for mp5 when you get full naxx gear or better in pretty much any (realistic) situation.

The post above was written with the changes of 3.1 in mind. While the balances proposed for 'balancing spirit and intellect' will need a small update, the logic presented remains the same.

Zusterke is 100% correct, the value of mp5 is not changing in 3.1 - you may see more of it on gear that has it in 3.1, but this doesn't reflect any change in stat weight by blizzard, just higher item levels or different approaches to itemization.

The simple way to illustrate Zusterke's point is to simply say: Spirit and Intellect are still both important. For paperdoll regen, spirit is still king - this is important to remember. However, changes to the game have resulted in a serious amount of mana regeneration coming from sources that don't reflect in your paperdoll regen -- meaning that spirit-based paperdoll regen is only one part of a larger regen mechanism.

The fundamental reason why I (and at the risk of speaking for him, Zusterke) hesitate to say something as blanketing as "Intellect is better than spirit now, period" is because Intellect regen is dependent on so many variables, and spirit based regen isn't. The largest portions of our intellect based regen are Replenishment and Shadowfiend: questions like "How often and for how long did I have replenishment?" or "Did my shadowfiend die early? How much mana did I get back as a result?" or "Do I have a resto shaman in my group for manatide? Did he use it?" reflect the type of variables and the extent to which they can affect your intellect based regen. Under good circumstances, Intellect is the best, however under all circumstances, spirit is the most consistent.

As a result, statements like that need qualification, for example: Intellect is better than Spirit, at realistic gearing levels, if you have access to all of these abilities (replenishment, shadowfiend, mana tide) and they're used appropriately and to their fullest extent. Intellect is still better than spirit in a variety of other situations as well, but the point is - the potential situations are so vast and varied, and exceptions exist- so it's safest to keep yourself with a solid amount of both, and it's also worth noting that the gear which exists currently, doesn't allow for truly vast differences in Intellect and Spirit, unless you're deliberately favoring mp5 gear, as a disc priest would.

Ty for clearing the Patch changes up... alot of healers on my server are changing over to MP5 gear and think spirit is getting nerfed so bad that they should abandon it if possible. With the Dual Spec coming out it will get interesting and bring a little more fun to the Priest since we can switch to DPS in shadowform at will (once switching gear) ala Outfitter mod. So I wont give up on my Spirit gear after all...

Thanks for this post! I'm pretty terrible at math and I've been reading through the EJ theorycrafting on the subject with my eyes glazed over.

I do have one question: do the returns on intellect and spirit differ between Holy and Discipline? It's been my understanding that for a Disc priest it's better to stack spirit as a Holy priest for the spell power bonus, and up to a certain point MP5 is slightly more effective than spirit for a Discipline priest?

Disc priests benefit more from intellect due to Rapture and Mental Agility. Therefor Disc priests have a lot to gain from stacking intellect. When stacking a lot of intellect, the value of spirit increases as well (as explained above). At about 1200 intellect unbuffed (even sooner), the value of spirit is the same as mp5 for disc priests under the toughest circumstances (for Holies I recommend stacking spirit sooner).

In 3.1 intellect increases slightly in value as the shadowfiend gets buffed and spirit decreases a little in value. Still, at about 1200 intellect you will see a comparable performance of mp5 and spirit though I recommend stacking a lot of intellect.

Can someone explain to me in dummy terms, should I value mp5 gear over spirit gear from 3.1 onwards? :p

I think the point of the above posts is to say that intel+spirit is the best way to go. Unless you have a specific disc build, with limited access to raid buffs, mp5 isn't going to do the job that stacking and balancing your spirit and intel will.

Yes and no, Zhaelia. The top post was created for pre-3.1 numbers, when you wanted 1:1 between spirit and intellect for best results. Currently, it's much better to focus on intellect (to a point, I believe Zusterke's mentioned 1200 int for Disc is a good figure... probably for holy as well) and then build spirit from there.

In 3.1 you can gear for 9:12 spirit vs int ratio to achieve an optimal regen (imo) if you want but you can easily take a higher amount of spirit or intellect depending on your preference. However, most of the explanation above still applies. It tried to explain under which circumstances which regen strategy works best and the strategies proposed above still work. I'll try to update the specific details to 3.1 over the course of this week.

As for your specific question: I can't give you hard rules like X > Y because depending on the fight and situation one strategy can slightly prevail over another but with end naxx gear spirit and intellect both beat mp5 under most raid circumstances. This doesn't mean mp5 on an item should be shunned, but stacking a bunch of intellect and spirit (with emphasis on intellect) will probably yield the best regen for your bucks in Ulduar.

You made a fine post, but I wish you would have added the following conclusions:

In epic gear and a 25 man raid you should never use:
+16 Mp5 food since +40 Spirit food is way better
+37 Mp5 flask since +125 Spell power or a combination of Int or Spirit or Draenic Wisdom Elixir and Spell power Elixir are far better.

The later is especially true if you are using Spell Power Gems and/or throughput (Spell Power/Haste/Crit) trinkets. Replace these first with regen stats before you stop using the Frost Wyrm Flask. If you feel you do absolutely need regen stats from your flask I suggest the BC-Int flask over the Mp5 flask.

Sorry, but since spirit and intellect scales, this type of regen has to be clarified deeper. Also saying that spirit and intellect gains with a ratio of 2:1 is best is wrong.

On my priest I stack int since I'm a disc priest. So my stats are around 700 spirit and 1100 int unbuffed. While we're using these stats, we distribute 100 devided over both stats. Then you'll see that with the formula discribed above that spirit will gives more regen no matter what. But here you're forgetting about replenishment and the mana that you gain for every point of int.

We have to calculate the total mana regen, so the factor "A" is important. Where A is 0.0167 means that I will get 221 mp5 from spirit regen while casting (221 = A * 700 spirit * 1100 int * 50% from meditation).

Replenishment is easy to calculate since the gain from replenishment form int or the gain in int is lineair. (Regen = int * 15 * 0.0025 * 5).

Last, add the gain in mana from just having int. So here it's hard to calculate since every fight is different. So I'm going to assume every fight lasts 10 minutes for the worst case scenario.

Result of mana regen calculations while casting with only meditation as regen increasing talent:

700 spirit; 1200 int; 505 mp5 from spiritregen
766 spirit; 1134 int; 504 mp5 from spiritregen
800 spirit; 1100 int; 503 mp5 from spiritregen

Here you see that because of replenishment, the difference between intellect and spirit is almost zero. For a holy priest, spirit would be best because of Holy Concentration. For a disc priest, intellect would be best because of Mental Strength.

For reference, let's go with about twice as much spirit as int:

1200 spirit; 700 int; 462 mp5 from spiritregen
1134 spirit; 766 int; 468 mp5 from spiritregen
1100 spirit; 800 int; 478 mp5 from spiritregen