Magical Blue spells and stacking resist rate

[eva00r]

I'm pretty 100% certain that Physical blue spells do not have any stacking resist rate but I don't know it for Magical ones. For some inspection, I killed Niddy as BLU/WHM, nuked him 27 times - resulted below.

Nidhogg takes 700 points of damage. Full
Nidhogg takes 496 points of damage. Full
Nidhogg takes 248 points of damage. Half
Nidhogg takes 600 points of damage. Full
Nidhogg takes 496 points of damage. Full
Nidhogg takes 703 points of damage. Full
Nidhogg takes 122 points of damage. Quarter
Nidhogg takes 496 points of damage. Full
Nidhogg takes 700 points of damage. Full
Nidhogg takes 496 points of damage. Full
Nidhogg takes 489 points of damage. Full
Nidhogg takes 350 points of damage. Half
Nidhogg takes 496 points of damage. Full
Nidhogg takes 70 points of damage. One-Eight
Nidhogg takes 216 points of damage. Half
Nidhogg takes 893 points of damage. Full
Nidhogg takes 59 points of damage. One-Eight
Nidhogg takes 700 points of damage. Full
Nidhogg takes 56 points of damage. One-Eight
Nidhogg takes 700 points of damage. Full
Nidhogg takes 496 points of damage. Full
Nidhogg takes 61 points of damage. One-Eight
Nidhogg takes 693 points of damage. Full
Nidhogg takes 123 points of damage. Quarter
Nidhogg takes 70 points of damage. One-Eight
Nidhogg takes 198 points of damage. Quarter
Nidhogg takes 70 points of damage. One-Eight

I'm not sure that this is the result of ONLY Mind Blast's stacking resistance or the system took Thunder IV, III, Burst II nuke into calculation as well. Because early on, BLM didn't nuke much since the fighters were called for on hold, letting PLDs generated a good amount of enmity first. However the last 15 minutes, there were a lot of SC-MBs and nukes by 3-4 BLMs and 1-2 RDMs. You'll see that my nukes were resisted quite often.

This data may not be fully reliable becuase I didn't capture Lightning Threnody and Suiton effect.

[Suiram]

Assuming you are asking a genuine question, and not just showing off your Nidhogg damage camouflaged as a question, all magic damage is affected by the NM cumulative resistance. The reason physical magic is not, is because the damage type is classified as physical damage. Nidhogg being a terrible test subject in itself, because of its 2H, but I'd probably guess that the 700s were full damage, the 690ish ones were "magic nerfed" and the 490ish ones were during his 2H, and possibly magic nerfed as well. It doesn't matter so much how far into the fight it is, unless it was a particularly short fight, since the magic damage resistance appears to decay rather quickly, so rather it matters how many BLMs were nuking at the same time as yours, and whose spells happened to land first.

[eva00r]

I won't try to show off 700 Mind Blast damage in BG forum, it's way too undergeared. Or if I wanted to I should have my in-game name captured as well.

I am going to clarify a bit more,
700 = Full damage with Burst Affinity and Memento Mori on
490ish = Full damage without those
>700 = Either Magic Burst or Convergence on

And I got 2 more questions
What do you mean by "magic damage resistance appears to decay rather quickly" ? Since I never play BLM or RDM ever and this is the first time I tried my BLU/WHM on HNMs - besides The Wyrm. What do you think a better test subject is ?

[Judai]

The Magic Damage Resistence literally disappears like 30s after nukes are done. It only comes in to play when several people are nuking at the very same time and a few moments after those nukes are done, the resistence is gone. The very first nuke in a MB set will hit full damage and every nuke after that will be nerfed just a bit but a few moments after all nukes have landed, the resistence that was buily up from the MB volley will decay and be gone.