Arcane Thesis dilemma

[Eldritch_Lord]

Well, picture this, a Sorcerer with much the same build that you had but instead of magic missile he throws lesser orbs of cold (with a quickended true strike form a wand, yes it is possible).

I hope that's a quickened sanctum true strike and not just a quickened true strike, or that he crafted it himself with metamagic reduction, because the latter is a 5th level spell and wands only go up to 4th.

On top of that he has cone of cold with Arcane thesis, Piercing Cold (no cold resistance and those who have immunities receive half damage), Flash Frost (+10 damage and area coated with frost), Sculpted, Still and Empowered. We're level 12 now but his average damage is about 98,75 (save DC 21 or so for half), with one sculpted casting. Then he casts Celerity....Is that overpowered? I think so.

First, Celerity is usually viewed as too powerful without a way to avoid the daze, or viewed as broken and banned with a way to avoid it, so that's part of your problem there.

Second, he may just be rolling high, unless he has some other boosters you haven't mentioned; the average damage for an empowered piercing flash-frost still sculpted cone of cold at 12th level is (12d6+10)*1.5, which works out to (42+10)*1.5 or 78 damage on average from a 6th level slot, not 98.75. For comparison, an unmodified disintegrate deals an average of 84 damage to one target at that level, an empowered searing split scorching ray with Arcane Thesis (Scorching Ray) deals (16d6)*1.5 or 84 damage out of a 3rd level slot to up to 4 targets, and any spell that deals ability damage or other penalties instead of damage is going to outdo both of them. I'd say focusing on cone of cold is fine.