Disruption shield doesn't work the way you think

[Berder]

I've played a bunch of archmages and never until now did I find out how disruption shield actually works. I may have died to not understanding this before.

To be clear, let's break it into cases.

1. >50% MP, disruption shield still has shield power. In this case it will absorb damage without costing any MP, until its shield power is gone.
2. >50% MP, disruption shield has no shield power. In this case it will absorb damage using your MP until your MP reaches half, then it will deactivate.
3. <50% MP, disruption shield has no shield power. This case can't be reached.
4. <50% MP, disruption shield still has shield power. This is the zinger. In this case it will *not* immediately deactivate. But nor will it absorb any damage for you. It will look as if you have full shield power, up until you are hit by an attack. Then it will deactivate (without absorbing the hit) and your HP will take the damage. It will also deactivate if you cast certain spells; mana thrust and arcane eye are examples. It won't deactivate if you just walk or use non-mana-using abilities. Certain spells, such as mana surge rune or time shield, also won't deactivate it.

This is what case 4 looks like:


My effective HP here is 366 (ignoring negative hit points) - it looks like 366+1291, but it's not. If something does 500 damage to me in this case 4 state I will die. In previous games I assumed, because it looks like this, that the shield power in this state will still protect me even though I'm below half MP. That's not true and the misunderstanding may have resulted in my death once or twice.

IMO this should be redesigned. One option, disruption shield could prevent case 4 entirely - so as soon as you dip below 50% mana the shield is gone, and doesn't show any shield power. This would avoid misleading people into thinking they are protected when they are not. For the other option (imo better) disruption shield could continue to work in case 4 as long as it has shield power, and only deactivate once the shield power is gone if you are still below half MP.

[Tradewind_Rider]

Hi!

Disruption Shield checks the shield deactiation in 2 circumstances:

1., on CallbackOnHit

(so basically if you are taking any damage that goes through the damage mitigation line)

if CallbackOnHit triggers AND you have less than 50% of your mana, then the shield will deactivate first,
before any damage reduction could trigger.


2., on using mana

if you are spending mana, AND if you have less than 50% of your mana (be aware, the spent mana is calculated here)
then the shield will deactivate.


So yes, you can be in this state, where you have less than 50% mana and you can still sustain the spell,
imo the talent should check it once per actor turn.

[Berder]

The problem with simply making disruption shield always turn off when below 50% mana, is autocast. If you have disruption shield on autocast, and depleted your mana, and rest, then what will happen is it repeatedly casts disruption shield only to deactivate it the next turn until your mana is back. That's why I think it's better to simply let disruption shield not deactivate when below 50% mana unless its shield power is already depleted. Besides, the purpose of letting it deactivate when below 50% seems to be to prevent it from consuming all your mana; as long as it still has shield power that's not a problem.

[Tradewind_Rider]

It's pretty easy to give it a pre_use tag, just ike the old Disruption shield had.
E.g. this way it will be only useable if you would have minimum 50% of your max mana.
Otherwise, it will be "silenced" like the Shatter Afflictions rune when you do not have any detrimental effects.

on_pre_use = function(self, t)
if (self:getMana() / self:getMaxMana() >= 0.5) then return true end
return false
end,

[trungaczne]

I think this could go to bug report because it's just misleading if the shield is up but doesn't work

[Effigy]

I don't think the mana check should come into play if the primary shield isn't depleted. Mana is only used to prevent damage after the initial shield has worn out, correct?

[Tradewind_Rider]

I don't think the mana check should come into play if the primary shield isn't depleted. Mana is only used to prevent damage after the initial shield has worn out, correct?

This depeds on the develpoers, what they want, but in the description of the Disruption Shield talent, there is:


"Dropping below 50% mana or reaching max energy storage will automatically deactivate this talent."


So: dropping below 50% mana OR ... will automatically deactivate this talent.

Therefore, it is intended for this talent to NOT BE USEABLE if you have less than 50% mana.

I have other issue also with archmage, so i will write them together.

[Berder]

Well, if the comment doesn't match the code, it doesn't mean the comment is right. Perhaps the comment wasn't written with consideration of Case 4.