Her ultimate, is also something I have a problem with, and in this regard, she's like Swain, at least from the way I've understood it. It's a number of shots, over and over, each hitting for it's individual damage, which when MR is built, lessens it's overall power considerably, because for all intents and purposes, it is a DoT.
When you are on the lower end of the sphere count and you fire it, it deals overall, less damage than a singular chunk ultimate, but when you're on the higher end of the sphere count, it has the potential to do more. There's only one problem though, Sphere's do not last long enough.
Mostly, these are my complaints about Syndra, and what I would like to see happen to her, if I'm wrong on anything damage calculation wise for her ultimate or something else, just tell me.
MR and armor doesn't work that way. Damage reductions are calculated as 100/(100+MR/armor). So, Magic damage reduction with someone who has 60 MR is 100/(100+60)=1/1.6=0.625, or 62.5%. That means that each spell does 37.5% damage.
So if the damage for each sphere is 100, and lets says 5 spheres for a "DoT":
100*.375+100*.375+100*.375+100*.375+100*.375 = 100*.375*5= 187.5
Now If we have a Nuke instead that hits only once for 500 Magic damage:
However, I do like the idea of having her spheres last longer.