Eh, that's not that part that worries me.
I hope you're not asking for recalculating attacks after every attack in case of a failed save? Looking at the number of attacks Dyson has going on, that would be...
Iskandar makes dex-based attacks, so he wouldn't have to change the rolls. On the other hand, his strength is abysmal, so if he fails those fort saves he falls helpless.
Oslecamo: Thanks for noting the dex drain amount. In addition to that, I need to know how many attacks hit (so I know how many fort saves to make) as well as how many of my crits were confirmed, for Blood in the Water.
Also a point to note in case it's relevant: Iskandar's melee attacks overcome half of any DR by default thanks to Legendary Might. I didn't note it in my spoiler. Sorry, it's been a while, and I'm trying to review all of what his abilities are. Apparently the DC's of his abilities are also +2 thanks to Essence drain, which would impact the save vs. Stagger and likely not much else.