I've been wondering about this for a while. I have a pet sorc and since Summerset I've seen it described that Mantle of Siroria is great, specifically by Alcast's Summoner build.
But Mantle of Siroria requires damage from a single target ability. My question is, for a pet sorc what are the single target abilities? I run a rotation with liquid lightning, blockade of elements, daedric prey, volatile familiar, and twilight matriarch.
Liquid lightning, blockade of elements, and the familiar pulse ability would all be AoE, damage, right? Only daedric prey would be the single target ability, and casting once every 8 seconds or so doesn't seem like often enough to get those stacks of spell damage you'd want with Siroria. Maybe the twilight tormentor ability? But I doubt it since it is a damage increase so it doesn't really target an enemy.
I run with Necropotence, Destruction Mastery, and a monster set instead of Necropotence, Siroria, and monster set since I don't understand the benefit of Siroria for a pet sorc.