User blog comment:JmLyan/CB1 Sorcia, the Spellbound/@comment-973379-20150318220128/@comment-7481207-20150319095419

Your Q calculation is off. It only scales with bonus mana, so her 1260 base mana at level 18 does not increase its damage, and Muramana damage is based of current mana, and that goes down pretty quickly. On top of that, that build is super late game, two stacked tears are usually not possible in a standard game, and then you have to build your 2 RoA as early as possible.