Shell Shield and similar damage reduction abilities?

[Jordicus]

Has any one else noticed that these abilities work stronger than indicated?

For example, I just battled a level 24 Spiny Terrapin. It casts Shell Sheild and the toolip on the buff icon states "reduce up to 50 damage from every attack". However, I have attacked with level 25 Immolate and the tooltip and spell description both state "deals 70 elemental damage every round". So the expectation should be that the Terrapin still takes 20 damage each round. But it never does..! Each tick of Immolate is completely blocked.

I checked and it seems other DOT attacks have a similar problem. And it seems to be all damage reduction attacks. Maybe the number is just incorrect in the toolip, but I'm not sure...

[Bistromath]

From what ive played around with and Damage Reduction Ability that blocks min of 50 damage will stop all damage from any DoT, included with that the Damage from weather effects.

Ive seen the DR abilites (blocks 49 damage or less) of pets in low 20s take reduced damage from DoTs, but they still take some.

So recap, if it says it blocks at least 50 damage then dots do no damage, if it dont block at least 50 damage then some damage will hit the target.

[Jordicus]

that's what i've thought as well, but i've seen some cases where it's different.

case in point, Jade Oozling ability Corrosion. Just had a battle with another Spiny Terrapin. Shell Shield is reducing damage by 54. Immolate (70 damage) is completely blocked. However lvl 19 Corrosion (21 Damage each round, all Damage increased by 54) is actually still getting a net 16 points of damage...

Something is not right somewhere....

[Mathew013]

This has been a problem (or a tooltip error) for a while.

My croc's Rip ability should be inflicting 78 damage per round, but as soon as a Shield-type spell is applied, the DoT stops.
It inflicts NOTHING per round. The rip effect is still there, for the follow-up ability Blood In The Water, however.

[Alfonzzo]

agree that something is weird with shields. with the aquatics, don't forget their racial reducing dots by 25%. That said, i'm not sure where the block gets factored in and suspect that may play a part in the weirdness. I suspect it's a question of when the block is applied.

I suspect the calculation is closer to this:
(base damage - shield) * modifiers
versus what seems more logical to me:
(base damage * modifiers) - shield

That would explain why 100% of the Glowing Toxin damage (6% damage each turn) gets through, or why Stampede effects do no damage regardless of what damage boosts are up.

this is largely untested, but that's what it feels like to me for now.

[Poofah]

Yes, I've tested this for most types of damage and modifiers, and that's largely correct. Addition/subtraction is generally done before any multipliers, so shields subtract damage before you multiply for e.g. the Stampede debuff, or for weak/strong damage based on the pet's type.

Doing the math this way works for direct damage and for delayed damage (e.g. Elementium Bolt, Whirlpool, etc.). But in the case of an aquatic pet with a shield taking damage from DoTs or from AoE such as Tidal Wave, the numbers don't quite add up, and I haven't figured out what's going on there.

*edit* Some additional info: the aquatic passive ability reduces DoT damage by 25% *before* addition/subtraction, such as the extra damage from Corrosion. This is the first example I've seen for a multiplier being applied first. The math for aquatic plus shield is still not quite right though.

[Jordicus]

Some additional info: the aquatic passive ability reduces DoT damage by 25% *before* addition/subtraction, such as the extra damage from Corrosion. This is the first example I've seen for a multiplier being applied first. The math for aquatic plus shield is still not quite right though.

that may explain a lot of the discrepancy. i'll see if that adds up in the next couple of battles

[Elmarc]

I have found more or less the same problem with shields vs swarm (the attack for 120 damage that is done by critters with 3 small hits of 40ish each time) even the stronger version (220 damage) doesnt do damage. Nor will the 100% damage buff help to get a hit.

PS my numbers might be a bit off, but its just to make the example

[Poofah]

Stampede or Swarm is an interesting case because the tooltip is slightly imprecise. It says it deals 9 damage, but it really deals 3 bursts of 3 damage. Build Turret is the same: it says 9 damage, but ingame it deals 3 little shots of 3 damage each. This detail becomes important because Shell Shield reduces each of those hits by 5, so instead of taking 4 damage, you take 0 (you actually take 0 damage 3 times--ingame it will appear as "block block block"). And, Shell Shield gets to reduce the damage from Stampede before you multiply for the Stampede debuff, so it's (3-5)*2, instead of (3*2)-5.

The way the math is done really favors Shields. Any time an attack deals damage in separate bursts, the shield subtracts damage from each burst. Examples include Triple Snap/Flurry/Quills/Thrash, any DoT, Tail Whip, Alpha Strike and Pounce (these are interesting because the damage pops up in the UI as a single hit, but in the combat log you can see that it actually does two hits, and shields subtract from both), the bonus damage from Lightning Storm, and double-damage abilities such as Conflagrate or Early Advantage.

Sandstorm is extra amazing because it does all this, plus it shields your backrow pets the same way, which reduces most AoE down to virtually nothing.