Stacking Threat Reduction

[savaughn]

For some bizarre reason, Daelo, one of the Blizz game designers, decided to answer a fairly random question in the raid forum. What's more, what he said there fairly directly contradicts the general impression on stacking threat reduction. Specifically:

- "Stacking" of threat reduction effects. Every single one of them I tested stack. This includes the Netherwind bonus, Arcane Subtlety, Blessing of Salvation, Nemesis Bonus, and Master Demonologist. However, note that they don't always stack in the way you might hope. You don't add all the percentages up, then apply the combined multiplier to the damage your spell does to obtain threat. So if you have Blessing of Salvation (30%), Master Demonologist (20%), and the Nemesis set bonus (20%), you aren't generating just 30% of your normal threat. The true number is something a bit higher. The specific details of the stacking are something I'll pursue further with the class team and programmers to make sure we're happy with how they're working, but the important thing is that each bonus does provide a significant threat reduction.

And later:

I did test Arcane Sublety. It stacks with Netherwind and Blessing of Salvation, too. I edited the larger post to reflect this.

http://forums.worldofwarcraft.com/thread.a...8&p=#post205139

Something to be aware of. I know I've been "corrected" that subtlety and BoS don't stack around here before so I think this is new info. My guess is that each threat reduction piece is being applied individually - from a programming perspective doing that would be easier than trying to keep track of a total overall reduction "state" and applying at the end. If that's the case then with, say, BoS, MD, and Nemesis instead of getting 30%+20%+20% for 70% you'd end up with a 30% + 20%*70% + 20%*56% for a total of around 55%. Similarly if you applied arcane subtlety and BoS this way you end up with around 58% reduction.

That's just a guess, though. To test it, we're gonna need a pally, a mage, and a priest w/o subtlety...

<edit: forgot - the other reason this would make sense is that the results are commutative so it doesn't matter what order you apply the reductions>

[Warlock]

Interesting. I hadn't got around to serious testing yet myself. Interesting that such a crucial mechanic as threat generation need checking into even by Blizzard :D

[oldmandennis]

Not threat generation, but threat generation reduction stacking, in a game where stacking is often case by case, and sometimes buggy? I'm not suprised they had to test it.

[Gurnsey]

<edit: forgot - the other reason this would make sense is that the results are commutative so it doesn't matter what order you apply the reductions>
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I've seen a trend in MMORPG's in the way this works (and it's a good idea) - damage reduction is multiplicative while damage addition is additive.

Additive vs. Multiplicative damage/threat reduction:

4 items/skills at 30% reduction each:
Additive = 30% + 30% + 30% + 30% = 120% damage reduction, or you take -20% damage. So, you are healed? No good (for game designers, much as we might like it)!
Multiplicative = .7 * .7 * .7 * .7 = .24, or you take 24% damage. Much better!

Having multiplicative reduction means you can never get to 0 or negative damage, no matter how many items you have on. Same with threat - what the heck would negative threat mean? Mobs like you?

Additive vs. Multiplicative damage bonuses:

4 items/skills with a 25% damage bonus each:
Additive = 25% + 25% + 25% + 25% = 100% more damage, or do 200% normal damage. Easy to balance, not too out of control.
Multiplicative = 1.25 * 1.25 * 1.25* 1.25 = 244% normal damage, or you do 144% more damage.

Additive damage bonuses mean that additional bonuses don't spiral the total out of control (EVE Online had a problem with this with Heat Sinks, which increased damage of your weapons; while having one 40% heatsink on your frigate didn't mean much, equipping 8 40%-bonus heat-sinks on your battleship means you did a whopping 1475% of normal damage...do you think that anyone equipped anything else there? Incredibly hard to balance).

[Skandranon]

For some bizarre reason, Daelo, one of the Blizz game designers, decided to answer a fairly random question in the raid forum.&nbsp;
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The original question, of course, was whether the Netherwind 3-piece bonus actually functions. His response was one of the worst Blizzard non-answers I've ever seen, which is that yes, it reduces threat equally across all levels. Tests that show rank 1 frostbolts with the bonus having full threat reduction and rank 10 getting less than 1% threat reduction thus show the bonus working as intended. Daelo says that the "way the AI uses threat is a secret" and since we don't know, the fact that people with and without the bonus get aggro at the same level of damage is fine.

In short: it reduces some internal value of threat, but not the likelihood that you'll draw aggro. Shorter version: doesn't work, we don't want to fix it.

[savaughn]

Tests that show rank 1 frostbolts with the bonus having full threat reduction and rank 10 getting less than 1% threat reduction thus show the bonus working as intended.
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Hey Skan - do you have a link for this? I'd be interested in looking at it.

[Skandranon]

Hey Skan - do you have a link for this?&nbsp; I'd be interested in looking at it.
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The original tests were eaten by the raids and dungeons forum, but references to new tests are made in the same thread as daelo's response.