I've got the strong feeling that this whole thing will devolve into a classical murder-mystery. The setup is just fitting far too well for it to be a coincidence. So my plan is a bit influenced by that assumption. It works perfectly fine without that hunch being right, but if my plot-sense didn't fail me, the whole thing will be twice as awesome for us playing along with it.
[X] Plan Setting The Stage
-[X] Preparation:
--[X] Viserys quickly fetches Aradia and moves with her to Anya and Mia. He uses Ancestral Awakening to learn Cultural Adaptation and Heroism, then Blood Wishes Harmonic Chorus and Arcane Concordance spells on himself to boost his caster level to 20 and allow him to Extend all of his following spell. While enhanced, he casts Nine Lives, Air of Nobility, Comprehend Languages, Cultural Adaptation, Heroism, and Grand Destiny(using Greater Shadow Enchantment) on each of them.
---[X] Tyene casts Neutralize Poison, Nondetection, and Wind Walk, on them and provides each of them with an acorn enhanced with a Fire Seeds spell so they inflict 15d6 damage when used.
--[X] Once this is done, he goes back to Hermetia and Shara to cast as many Divinations for them to support their efforts (see Execution phase) as he has Bloodwishes left.
--[X] Then he Teleports over to SD, deposits the small marble cube there for Dany and takes the bedroll. He messages Dany with her part of the proceedings and looks upon the Wayfinder to get a rough idea of where the potential westerosi agent currently is. Knowing if he is in Lys, Westeros or mainland Essos is enough detail.
--[X] He then goes to the Fungus Forge to have a short nap to replenish his spells. He takes a quick nap there to replenish his spells, then picks one of the Erinyes to help him with the next part.
-[X] Execution
--[X] Hermatia and Shara will try to exploit the ruckus caused by the botched assassination to further their own work. Namely turning people to their side and sowing distrust among the Spicers.
--[X] Aradia, Mia and Anya will infiltrate the solicitors office to find out more about his clients and dealings.
--[X] Dany will pick up the marble cube in the evening, then take it with her into the dream. There she dreamcasts Touch of History to learn enough about the suspected Lannister / Baratheon agent that she can find his dreams. She will then visit him in his dreams and extract as much information about his work as possible. Most important is to know who his backers are and who reacted favorably to his offers. Lastly, she wipes his memory of the visit, leaving him none the wiser.
--[X] Viserys and the Erinyes will Teleport to the manse and infiltrate it in disguise.
---[X] Viserys will wear a richly, though sensibly embroided robe of silk, with the Serpents Sin appearing as a matching golden silk-cloak. The style should be eastern, a blend between Qarthene and Yi-Tiish styles. The Weirwood Staff will be disguised as a sorcerers staff of eastern style.
---[X] The Erinyes will have a matching disguise, appearing as a well cared for assistant and possibly bodyguard.
---[X] He will introduce himself only vaguely, stating that had wanted to make a offer to the deceased and might want to make the same offer to one of his heirs. Thus he wants to observer the proceedings and talk with the attendants afterwards. Play the part of the haughty sorcerer, being respectful of the people he needs something from, but ultimately an eastern snob that considers himself far above them all.
---[X] If pressed enough or if Viserys feels it advantageous to reveal this bit to one of the attendants, tell them that after a long time of tracking it down, he had learned that he had come into possession of a certain item, but stay utterly vague on what that item actually is. As he is a noble man of means, he is willing to offer a good price to whoever inherits the piece in question, but will not reveal what item it is, as he doesn't want a bidding war.
---[X] The Erinyes is mostly coming along as a extra set of hands and a set of True Sight eyes.
---[X] Note: The goal here is to present a intriguing persona that apparently has both wealth and magic to offer to anyone who gets close to him. At the same time, he will look the overconfident foreigner, sparking the thought in some of the attendants to screw him over for their own gain. The availability of magic also means it's easy to see how he learned about this event and came to the manse despite not being officially invited. Basically, present everyone with a opportunity to sate their greed for wealth and power, thus making everyone not only accepting of Viserys presence, but actually looking forward to it.
Thoughts?
Edit: Credit for
this part to
@Goldfish.