Moonglow vs. Furor

Moonglow or Furor? The age-old question: Is it better to save mana or gain mana?

This question has been answered many times before, but the answer tends to fall under one of two extremes: it either references a complex formula which goes right over my head, or it gives an absolute X is better than Y without much explanation. I’m going to try to answer the question in a way that falls in between those two extremes. I’ll answer the question in layman’s terms with concrete examples of how the two talents affect your mana pool.

First, let’s look at exactly what the talents do:

Moonglow – Reduces the cost of your damage and healing spells by 9%.

This is a very basic bonus. The benefit you’ll see from Moonglow depends entirely on how many spells you cast and how much mana they cost. The more mana you spend, the more benefit you will see from Moonglow.

Furor – Increases your maximum mana by 15%.

Furor is a little more complex. Besides the flat mana increase you get, you will also see a bonus to any mana regeneration that is based on your mana pool, such as Revitalize, Replenishment and Innervate. Furor is a talent that scales with gear – as your mana pool increases, so does the benefit you gain from Furor.

So how do you tell which talent will create a more positive effect on your mana? With math!


Let’s look at Moonglow first. To figure out how much mana you can save with Moonglow, you need to have an idea of how much mana you spend on any given fight. To do this, I looked at random 30 second snippets of boss encounters and broke down how many spells I cast and how much mana they cost. Here’s one example:

Sample 5 Cost w/o MG Cost with 3 MG ย Mana Saved
Rejuv x7 26089 23740.99
SM x2 3727 3391.57
WG x3 15094.35 13735.86
N x4 7454 6783.14
LB x2 2608.9 2374.099
54973.25 50025.66 4947.59

I also cast 2 Regrowths during that time, but left out their mana cost to account for Omen of Clarity procs (I assumed a rate of 2 OoC procs per 30 seconds).

After looking at 5 random samples, I found that 3 points in Moonglow would give me an average mana savings of 4823.5 every 30 seconds.

Looking at different fight lengths, Moonglow saves:

Mana Saved in:
3 minutes 28941
4 minutes 38588
5 minutes 48235
6 minutes 57882
7 minutes 67529
8 minutes 77176
9 minutes 86823
10 minutes 96470


Now let’s look at Furor. I looked at the impact Furor would have on a mana pool of 100,000. First, there would be a flat bonus of 15,000 mana. Second, there would be an increase in mana regeneration effects.

  • Replenishment returns 1% of total mana over 10 seconds. An extra 15,000 mana would mean an extra 150 mana from Replenishment every 10 seconds.
  • Revitalize returns 2% of your mana whenever it procs. It has a 12 second internal cooldown, but from examinations of my own logs I found an average proc rate of once every 13.5 seconds. An extra 15,000 mana would mean an extra 300 mana from Revitalize every 13.5 seconds.
  • Innervate returns 20% of your mana and has a 3 minute cooldown. An extra 15,000 mana would mean an extra 3,000 mana from each Innervate.

I looked at how much extra mana would be regenerated with a base mana pool of 100,000 over a 3 minute fight:

Mana with 3 Furor Difference
100,000 115,000 15,000
Mana return over a
3 minute fight
Replenishment (18 occurrences) 18000 20700 2,700
Revitalize (13.33 occurrences) 26660 30659 3,999
Innervate (1) 20000 23000 3,000
Extra mana regenerated from Furor 9,699

Add that 9,699 to the flat 15,000 mana increase and 3 points in Furor would gain you 24,699 extra mana over a 3-minute fight. I then expanded these figures to account for larger mana pools and longer boss fights.

My full calculations are available in this spreadsheet.


When all the math was done, I compared the numbers for Moonglow and Furor and put them in a pretty graph.

Moonglow vs. Furor graph

Things we learn from this:

  • Furor gets better with larger mana pools.
  • Moonglow gets better with the amount of spells you cast. It gets better in relation to Furor as the fights get longer.
  • At current mana levels Moonglow will provide more of a benefit than Furor on any fight longer than 3 minutes.
  • Furor will not become competitive with Moonglow until our mana pools start hitting 150,ooo (at least) and even then, only on the shorter fights.

I hope I’ve helped to clarify the issue for those people (like me) who want to understand the reasons why one talent is better than the other without doing too much math.

*Disclaimer: I did not account for temporary Intellect increases in my Furor calculations. The temporary mana increases make only a few percent difference. For example, on a 3-minute fight with 100k mana, Power Torrent procs would increase Furor’s mana regen by about 4.9%. As mana pools increase, this number goes down.ย  Adding in the temporary Int boosts does not affect any of the numbers enough to make Furor better than Moonglow for any fight length or mana pool. And I’m all math-ed out.*

Thanks to Hamlet for reviewing my spreadsheet. For those looking for more druid theorycrafting, I suggest downloading Hamlet’s TreeCalcs. Thanks also to Zosima for making sure my math-to-English translation made sense. ๐Ÿ™‚

16 responses to “Moonglow vs. Furor

  1. This was a really great post, Jasyla and I’m glad to see more bloggers are starting to tackle the math behind things to get to the bottom of what’s really best for ourselves and the classes that we play.

    It’s kind of fun, isn’t it?


    • Thanks Oestrus ๐Ÿ™‚

      Tackling math when there are people out there way better at it than I was a little intimidating, but I’m happy with the post. I hope people find it useful.

      • I think it also helps when you walk them through the math. There are some bloggers who get really into the formulas and the x + 2 = 7/12 ( abc) and you get lost in it all.

        But if you can take a reader’s hand and walk them through it, show them how you came to your conclusions and make it seem less intimidating that says a lot about you to them. I think that’s what people want to see.

        • For sure. Heck, it helped me a lot walking through the math myself. It’s one thing to read “Moonglow is better than Furor, take it” and quite another to be shown why it’s better in terms that are relatively easy to understand.

  2. Another really great post, thanks Jasyla. Definitely a question worth asking and I feel humbled by and grateful for the amount of thought that you’ve put into this answer. I know for myself I’d be more likely to take Furor as a simple “I like more mana” gut reaction, and I tend to shy away from cost reduction spells, thinking that I can regulate myself in how much I cast better than any talent. Unfortunately I also think that this may actually hamper my healing in that I get stingy, fearing that I will run out too quickly, which leads me to dole out heals too slowly or only when absolutely necessary, which is usually too late. Thanks again, for making me think!

    • Thanks Twodzae, glad the post gave you something to think about.

      I don’t think trying to throttle the amount of heals you cast is the best way to save mana. Obviously, you don’t need to be casting all the time if it isn’t needed (though I do – I’ll spam Nourish if no healing is needed, I can’t help myself), but making yourself cast less than you need to will lead to trouble. It can be difficult to watch your mana pool get smaller when speccing out of Furor, but I’d give Moonglow a shot.

  3. Jas fantastic post. Those graphs were a real eye opener. Heh heh I know what you mean about spamming nourish – but tell people that it’s because you’re keeping harmony up rather than you can’t help yourself ๐Ÿ˜›

  4. Just to add to the discussion, I usually take one point in Furor simply for the ability to immediately Stampeding Roar after switching to Cat form instead of having to wait a few seconds for energy to generate. This utility is very useful to the entire raid, so I take the small drawback ๐Ÿ™‚

    • That’s a good point.

      Though in my raiding experience, whenever I use Stampeding Roar I usually have a spare second or two to wait for my energy.

  5. Hi, i just wanted to add that, while Moonglow in itself clearly seems a better talent than Furor, you may want to take into acount the additional cost of having to spend 3 points in Nature’s Grace in order to reach Moonglow, whereas with Furor these points could be better spent in the Restoration tree.

    • Nature’s Grace is an excellent talent and a sizable output increase, it’s a very good use of 3 talent points. I don’t consider having to take it to get to Moonglow to be a deficit in any way.

  6. with T12 2 piece bonus, how does the extra 1% base every ~2.5 seconds not to mention the insane mana return blanket lifebloom in treeform yields

    5% more base will increase this mana return

  7. Pingback: Resto Druid Tips for Ragnaros « Heart of the Wild

  8. Frostyspeed

    I would just like to point something out, i looked at the graph (not the math unfortunately yet). I think you missed something out. Have you taken into account when youre channeling a spell like tranquility you dont get any benefit from moonglow for 8s, and then your life blooms will likely fall off making you re-apply them and that makes it even a bigger loss. (As lifebloom with moonglow is only 40 mana reduction per cast).