If you’ve been paying attention to the PTR patch notes, you’ve probably noticed that there’s a big change coming in 5.4. I’m not talking about the change to Grand Crusader, which is mostly irrelevant to how we gear and spec. I’m talking about the 30% nerf to Sacred Shield and the 40% buff to Eternal Flame.
The nerf to Sacred Shield is understandable – it’s been head and shoulders above our other level 45 talents, and it scales very well with the extreme amounts of haste we’ve been stacking. Blizzard probably didn’t anticipate the level of haste-stacking we’d be doing (though to be fair, neither did most of the community), which explains why they have to dial it back a bit to keep it in line. The buff to Eternal Flame was less expected, but makes the tier much more interesting again. We’ve mostly ignored Eternal Flame in previous patches because it couldn’t keep up with the raw mitigation of Sacred Shield.
What many people don’t realize that Eternal Flame has interacted with Bastion of Glory (BoG) since around patch 5.1 via an undocumented change. The 100% buff when self-cast in 5.2 was another fairly large buff in addition to the BoG interaction. In patch 5.2 and 5.3, Eternal Flame’s HoT produced a little more healing than Sacred Shield provided in absorption. But as I said at the time, the healing would have to be significantly larger than the absorb effect to offset the opportunity cost of having to spend holy power, and thus, sacrifice Shield of the Righteous uptime.
The 5.4 changes move the goalposts, though. First, let’s note that the sheer size of these buffs and nerfs are pretty huge. This isn’t a minor rebalancing; Sacred Shield is getting slashed by nearly a third, while Eternal Flame is growing substantially. When casting EF with 5 stacks of BoG, each EF tick will be almost twice as large as a Sacred Shield absorption bubble. And remember, you’ll get two EF ticks in the same time period it takes to generate one Sacred Shield bubble. So the EF HoT has about 3-4 times the throughput of the Sacred Shield absorb. We’re no longer comparing equal amounts of healing and absorption.
The second change that comes into play is the Tier 16 4-piece set bonus, which removes the opportunity cost of Word of Glory and Eternal Flame if we have 3+ stacks of Bastion of Glory. That’s a big deal. Sacrificing a SotR for a WoG is a tough trade when it comes to smoothness, and that’s traditionally kept Eternal Flame from contending. But being able to use EF without sacrificing SotR uptime – and even increasing SotR uptime if Divine Purpose is talented – is a game-changer.
Either one of these effects may have been enough to make EF a contender in 5.4. Together, it’s hard to imagine even speccing into Sacred Shield. But we can do better than speculation; we can fire up SimC and see exactly how much of an effect these changes will have.
A Note on Overhealing
If you ask a random paladin why Sacred Shield was stronger than Eternal Flame during most of Mists of Pandaria, one of the most likely answers you’ll get is some variation on “because absorption is better than healing” or “preventing damage is better than taking it and healing it up.” Traditionally, this mindset has been ingrained in tanks and tank theorycrafting for the better part of the game’s life cycle.
Meloree summarizes most of these points rather well in this forum post, but in short, absorption effects tend to be more efficiently utilized than healing. Absorbs aren’t used up on avoided attacks and partial absorbs can apply to subsequent attacks, while partial overheals are “wasted.” And of course, since absorbs apply before the damage is dealt, they act as a first line of defense that often makes subsequent healing unnecessary.
But Mel will be the first person to tell you that there’s a hidden assumption in there – all of those conditions apply when the absorption and healing is roughly the same magnitude. Absorbs are better than healing point for point, because they tend to do a better job of being there when you need them, but a really large heal can still do more for your survivability than a weak absorb.
Also, if we’re rigorously analyzing the situation there are a lot of external effects that we need to consider. For example, do those absorbs affect how your healer plays, or would they be tossing a heal on you with that global cooldown anyway? If the latter, then it’s tough to say whether your absorb was really “efficiently utilized.” As far as World of Logs is concerned, your absorb applied first, so it was very efficient. But if it just creates larger overhealing for your healer, was it really a significant survivability gain? If you have several HoT ticks that overheal because of a full Sacred Shield absorb, is it really fair to say that the absorb was 100% efficient and the HoT ticks were 100% overheal?
In practice, Sacred Shield’s efficiency is a bit overstated due to the way logging works, which is related to how absorption effects are consumed. It’s often reported as highly efficient because the overheal it creates is shifted into other heals. But it’s probably fairer to recognize that a good chunk of Sacred Shield ticks are irrelevant, and share some overheal burden with the healing effects that they preempt.
Further, there’s a general attitude that overhealing is a bad thing and should be avoided – that those heals were “wasted.” While mana and/or GCD efficiency ties into that argument, I think it’s not fair to toss them aside so casually. To illustrate that idea, if you had a Lay-on-Hands-esque HoT that healed you for half of your health every 3 seconds, it would probably generate an awful lot of overhealing – possibly 70% to 80%. Would that make it a bad ability? Of course not, it would still be massively overpowered. While the majority might be overhealing, the fact that you effectively received a Lay on Hands during every 6-second period would also make you damn near invincible. Any sudden spike would automatically be countered with a Lay on Hands, without any effort on your part!
The lesson here is that steady-state overheal measurements are about as useful as steady-state damage intake measurements – that is to say, not very useful at all. Overhealing is only part of the assessment; we also need to consider throughput, and more importantly when that throughput occurs. I’d easily take the Lay on Hands HoT over a weaker absorption effect because even though it’s high overheal, it’s also high throughput during a spike event. It doesn’t matter if the absorption effect is 100% efficient, because it does less for me during those dangerous spikes than the overpowered HoT.
And that’s essentially the choice we’re making between Sacred Shield and Eternal Flame. Sacred Shield is the steady, efficient absorption effect. Eternal Flame is the overpowered HoT. The only question is whether the magnitude of difference is great enough to make us prefer Eternal Flame over Sacred Shield.
TMI to the Rescue
Luckily, theorycrafting has come a long way this expansion. In previous expansions, we might have to estimate an amount of overhealing for EF and do some hand-waving math to figure out whether that’s more effective. In fact, we’ve had to do similar things earlier this expansion with the MATLAB code. But those times are behind us, because we have TMI.
While it may not be immediately apparent, TMI essentially ignores gratuitous overhealing. Why? Well, consider what happens if you avoid a bunch of attacks in a row. Your damage taken during that period is essentially zero, but you have lots of HoTs or healing effects happening. When you perform the TMI calculation, you take the moving average and get a negative number. Then you subtract one to get an even more negative number. Then you raise 3 to that negative number and get a really small value, which you add to your TMI collector. So events where you have a lot of overhealing contribute very little to your overall TMI.
On the other hand, if you take a lot of damage, such that even after those HoTs and healing effects the moving average is near 100% of your health or larger, that exponentiation generates a very large number. In fact, the bulk of your TMI score is likely due to exactly these sorts of events: a handful of 6- to 10-second segments of each iteration where you experienced a spike. Throwing extra healing at these spike periods makes a big difference in your TMI. But the rest of the iteration produces a nearly-negligible background that doesn’t change much no matter what amount of overhealing you throw at it.
So in some ways, TMI is the ideal metric through which to filter overhealing. It basically ignores the overhealing that occurs during safe times, but properly counts the healing that occurs during a spike event. An ability that generates 90% overhealing will still perform well in a TMI measurement if it’s really good at saving you from or preventing spikes.
“Dumb” EF Usage
First, let’s consider some results I generated a few weeks ago. I call this section “Dumb” EF usage because in these sims I’ve made no attempt to tailor EF’s usage to incoming damage. We want to compare a player keeping Sacred Shield active to a player that uses Eternal Flame as a similar maintenance HoT, and blindly refreshes that HoT when it’s near expiration.
For these sims I used the trunk build of Simcraft, which should now be equivalent to v530-7. The build I used had all of the 5.4 changes implemented through PTR build 17116.
I used the following action priority list:
which is just the SimC default with a line appended to maintain Eternal Flame, but only recasts if we have 4+ stacks of BoG. I used Slootbag’s character as our test subject and pitted him against the T15H25 boss. The only thing I changed is which L45 talent he had selected (EF or SS).
Here are the links to the html output in case anyone wants to pick through them with a fine-toothed comb:
Sloot – EF – 5.3
Sloot – SS – 5.3
Sloot – EF – 5.4
Sloot – SS – 5.4
Sloot – EF – 5.4 w/ 2T16
Sloot – SS – 5.4 w/ 2T16
Sloot – EF – 5.4 w/ 4T16
Sloot – SS – 5.4 w/ 4T16
For those who want the TLDR summary, here it is.
5.3 Results, 4T15:
5.4 Results, 4T15:
Note that this is with his current gear, i.e. without 4T16 (but with both T15 set bonuses), so it’s a simulation of what will more accurately reflect the first week or two of progression. Also note that due to how SimC does its HPS accounting, the Sacred Shield absorption is being included in the HPS value while also reducing DTPS.
The buff to EF and nerf to SS clearly shift the balance in favor of EF by a fairly large margin, even without the effects of 4T16. It’s also worth noting that Sloot’s EF uptime in these sims is 97% or better. Since we’re only casting EF if we have 4+ stacks of BoG, this means he’s got enough haste to generate 4+ stacks every 30 seconds (more on that later).
We can artificially disable T15 set bonuses and enable T16 set bonuses using the code:
Doing that, we get:
5.4 Results, 2T16:
5.4 Results, 4T16:
Note that TMI goes up by disabling the T15 bonuses, moreso for the EF setup since it’s getting a significant benefit from the 2-piece (~45% uptime). It looks like EF is stronger even without the 4-piece, but the 4-piece clearly makes it a lot stronger while having no effect on SS.
However, this action priority list doesn’t include any line to simulate emergency WoG usage, so the comparison isn’t entirely fair. We can do a little better.
“Smart” EF Usage
We could try and include emergency WoG usage with a line like
Which would fire off a WoG if you took over 80% of your health in damage in the last 5 seconds. The idea is that this simulates emergency WoG usage as well as possible within the confines of the simulation. While we can’t accurately model healer reactions to your health bar or your own go/no-go decision making based on incoming healing bars, in both cases because we don’t have a healer in these sims, we can at least try to minimize TMI by burning a self-WoG whenever we’re in the midst of a spike.
This also should help simulate the penalty we pay by not having those BoG stacks banked for emergency heals. When we refresh Eternal Flame, we’re putting ourselves in a position where we don’t have a large emergency heal banked for the next 10-20 seconds, and that should have some sort of associated opportunity cost in terms of TMI. In theory, we’ll be able to see that with this sort of conditional added.
If we put that line directly after Eternal Flame in the action priority list, we get results that look like this. I didn’t have the simc file from the first set of tests handy, so I ran two baseline sims without that line for comparison. The setup should be relatively similar to the first, though.
It looks like including those emergency WoGs has helped narrowed the gap between the two results, even accounting for the Divine Protection “squish.” Eternal Flame’s TMI actually went up here because we’re casting it more often, sometimes with only 4 stacks of BoG, and thus negating some of the efficiency we had before. But Eternal Flame is still coming out ahead, even without the T16 4-piece effect. It seems like the loss of our ability to emergency heal is more than offset by the sheer throughput we have in the EF HoT. Being able to throw off a 500k WoG in an emergency isn’t as big of a deal when you’re getting 300k or more of that through a HoT.
And of course, if we artificially enable the T16 bonuses and disable the T15 ones, EF continues its dominance:
We could try to optimize this even further by constraining EF to only be cast immediately after we take a melee hit, ensuring that it’s applying the base heal effectively. In my limited testing, I wasn’t able to produce a strong TMI change with that (essentially adding an “incoming_damage_1s>health.max*0.4″ conditional and extending the allowed refresh period). I think I could produce some improvement with finer tuning of the two parameters, but probably not enough to be too significant.
But this also highlights a major difference between the sim and real raiding. Since we don’t have a healer, it hurts a little more to delay EF until a big spike, because it deprives us of that passive HoT ticking during some of the smaller spikes (or creates smaller spikes because the HoT isn’t there to counter them, depending on how you want to think about it). In a real raiding situation, you have other HoTs and healing sources to cover that damage, so we should get a little more effectiveness out of sitting on EF and using it to instantly respond to the next melee attack. In other words, delay it for a second or two (or longer if you get a string of avoids) to make sure that the base heal is efficiently used, which may save your healer some GCDs over the course of an encounter.
In any event, it’s looking like EF is going to be stronger than SS in most situations in 5.4
I do want to mention that there’s a minor caveat here: in all of these simulations, Slootbag had enough haste to ensure that he had another 4- or 5-stack of BoG with which to refresh Eternal Flame before the time came to refresh it. If he didn’t have that much haste, one would assume that EF loses some potency.
However, in my simulations that didn’t really seem to be the case. While lowering Sloot’s haste artificially, both TMI values went up, and Eternal Flame uptime fluctuated within the 90% decade. But Eternal Flame was still consistently beating Sacred Shield by a large margin even as low as 24% melee haste. It’s hard to imagine having less haste than that, since you can already exceed that value with full stamina gemming/gearing. So there may be a relevant haste threshold beneath which Sacred Shield becomes preferable, but it’s not likely to be relevant to anyone stepping into normal- or heroic-mode T16 content on day 1.
Note also that all of these sims were with Divine Purpose talented; it’s entirely possible that DP is what keeps EF afloat at 24% haste, and that speccing Holy Avenger or Sanctified Wrath will reverse the paradigm. I just didn’t have time to test all of those permutations thoroughly.
The simulations I’ve run here seem to be strong evidence that Eternal Flame is the new hotness, and Sacred Shield will merely be an also-ran in 5.4. While that’s a fairly accurate statement for the bosses modeled here, it’s worth noting that real bosses vary. In particular, effects that test your instantaneous effective health will tend to reward absorption effects more than healing, because those absorption effects are a temporary effective health boost.
For example, one-shot effects like Talon Rake and Decapitate may still lead you to prefer Sacred Shield. There’s a reasonable chance you’ll be topped off before the effect, and the extra absorption may just be enough to survive an otherwise-fatal blow.
What we’ve generally modeled with TMI bosses is slower trickle-down deaths from successive melees, which tends to favor the raw throughput of 5.4′s version of EF, as we’ve seen. And while I think that’s a more reasonable model of tank death for most progression tanks, it may not match your most common death scenarios.
As always, your mileage may vary. You’ll have to make the decision about which talent to take based on fight mechanics; obviously, if there’s a mechanic that strongly favors SS, don’t hesitate to take it. It’s not terrible in 5.4, it’s just nowhere near as good as it is on live servers currently.
There doesn’t seem to be any meaningful haste threshold at which EF eclipses SS, at least when Divine Purpose talented. I’m sure that we’ll revisit that topic down the road, though the T16 4-piece interacts so strongly with Divine Purpose that we may see most progression raiders taking it anyway.
One thought that keeps coming to mind as I review these results is just how far ahead EF seems to be. It feels like the 30% Sacred Shield nerf or the 40% Eternal Flame buff would have been sufficient to make the two equally valid choices in that talent tier. But the combination of both effects seems to just swap the two; rather than Sacred Shield being the hands-down, no-brainer choice that all paladins take, 5.4 just puts Eternal Flame in that spot.
It’s sort of disappointing in that sense. While it’s nice to have a new mechanic to fool around with in the last tier, the ideal goal of the talent system is to make all three choices viable (or at least in this case, EF and SS, since we generally ignore Selfless Healer). But rather than having an interesting choice between EF and SS, the 5.4 changes spin the wheel too far in the other direction. We still don’t have equally valid and interesting choices in that tier.
Although I’m not sure we’ll ever see that happen due to the nature of the three talents in that tier. I could imagine balancing Eternal Flame and Selfless Healer, because they both provide different ways to produce extra healing. But balancing either with Sacred Shield is tougher, because it’s an absorb. Even if they all produced identical TMI values, we’d probably lean towards Sacred Shield – it’s an absorb, essentially passive, generally higher DPS, less reliant on perfect play. It’s just safer than the other options if they produce similar results. I still hold out hope that next expansion, Sacred Shield will become baseline for Protection and we’ll get a third healing option in that tier. I think that we have a much better chance of getting three interesting and equally viable options in that situation.