More defensive mana options
say i have 
now i want to add mr, armor and mana
i could get 
but then im exceeding cdr cap.
if i get 
then im getting more mana and more cdr than i care to have and don't have enough armor.
I could get 
, but the support aspect to it is crap if i plan on using it on myself, especially without utility tree.
i miss the old banshee's veil for this sort of build.
this build could work fine with the old banshee's
/ 
Maybe there could be a duo resist item with mana, something like zzrot,GA but with 200 mana on it. Say with 45 mr, 45 armor.
rip:
V3.10:
Recipe changed: Spectre's Cowl.png Spectre's Cowl + Ruby Crystal item.png Ruby Crystal + 875g = 2750g (total cost increased from 2520g) Old recipe: Negatron Cloak item.png Negatron Cloak + Catalyst the Protector item.png Catalyst the Protector + 600g = 2520g Health increased to 450 from 400. Magic resist increased to 55 from 45. Mana reduced to 0 from 300. New Unique Passive: Grants +45 health regen per 5 seconds for up to 10 seconds after taking damage from an enemy champion or when the spell shield breaks.
would have less than before at 250 mana as opposed to 300
i would modify catalyst to give 250 mana and cost like 1125 gold instead of 1200.
giving 800 mana at 10 stacks this will be the least of your worries. (especially now that he doesn't need cdr he can just tack roas)
to SR