[X] Summon the independent Artificer Uniila that acted against you on many an occasion, in revenge for taking her sister captive and bound by powerful magics. -[X] Apply divination beforehand on a very minor chance she doesn't have a Mindblank. --[X] If she doesn't, plan around the fact accordingly (more Divination). -[X] Summon in Snare, with all Companions available present - utilizing Rings of Spell-Battle to maximum Counterspelling effect, while bombarding with all spells capable of non-lethal takedown. --[X] Apply additional precautions, like setting a carefully arranged Refusal spell upon the Snare chamber and layering Ghoul Glyphs as closely within the Summoning Circle as possible. --[X] Have the entirety of the cage surrounding the summoning circle covered in Hardened stone - rendering the metal beneath it immune to effects that would otherwise instantly corrode or melt through it, like the blood of the Fiends you fought over the Mercury Lake. --[X] Also make sure to be ready to act against any effects that may block line of sight - like a smoke bomb, for example. ---[X] Have the casting Companions circled around the Snare's summoning circle, so as to ensure more easily keeping her under fire even if she somehow leaves the circle; or puts up a LoS-blocking effect. ---[X] Have the melee Companions spread out around the room in a fashion that would impede Uniila from running in any direction if she manages to escape the circle and the cage- have a Companion capable of intercepting and swording her in moving distance, ideally also intercrossing each-other's segments of the room, so that they could attack from several angles.