Eligos stops mid-stride as Kushnak begins. His face turns grim as the half-orc talks.
"I will provide whatever explanations I can," he says, less calmly than before. "The parlor, please. We will take as much time as you need, so begin wherever you wish."
Speaking in turns, you relate the events of the last few days: Erdolliel's replacement after meeting with the city guard; "Nethezar" stabbing Tarquin at the Crooked House, and the subsequent battle with the merchant; the surrender to law enforcement, and being moved to the Sodden Hold warehouse during the night; Martal and Regim; Ilya Starmane; the other prisoner in the cells, who seemed to have nothing but insane ravings to tell; the incident with the cube, the four alien-like humanoids, and the deaths of Bazrim and Eskard; the area beneath the Sodden Hold; more of the creatures; finding the "real" Erdolliel; the planning room, with the map of the Free City; Nethezar's death and revival (though Nethezar skirts discussion around the details at the temple); the gem and the contraption that created it; the fake Allustan; the notes and other documents in the fake's bedchamber; the drow, with the yellow phosphorescent fungus; what the speak with dead spell revealed; and the illithid.
Eligos purses his lips as he listens intently, but he never interjects until the telling is complete.
"You have done more in the last few days than many adventurers do in a career. Those creatures are, indeed, doppelgangers. They are, obviously, natural spies and assassins. While they tend to thrive on manipulation, I've never heard of them amassing in that great of numbers, or acquiring as much influence as they have in the Free City. Their ability to shapechange is natural, not magical. That is why Nethezar could not dispel the merchant. The merchant, of course, was surely a doppelganger as well, but rendering it unconscious does not force it into its natural form like killing it does.
"They also have the natural ability to read surface thoughts. This makes their possession of these gems even more dangerous, since they need no magic to access the memories within.
"It is, quite frankly, beyond me to investigate the nature and extent of the doppelgangers' infiltration. But, of course, there are those who thrive off of that work. If you can find an investigator, perhaps with the city guard, that has not been... compromised... hopefully something can be done to repair the damage that has been done. Unfortunately, especially with the possible existence of more of these gems, the only way to ensure that someone is not a doppelganger is through true seeing."
Eligos pauses a moment, slips some tea, and sighs. "As terrible as that all is on its own, the involvement of an illithid compounds the problem immensely. This note,"[sblock=Note]I have a task for you, thrall. Meet me at the sewer junction beneath the cold forge and I will give you the details. There are some troublesome small minds that must be removed. Signed with the same symbol that was on the fake-Allustan's forehead.[/sblock]"It is clearly indicative that the doppelganger leader was itself a pawn of the illithid."
As Eligos continues, he finds a book and shows you a few detailed drawings. "Illithids, or mind flayers, are evil and manipulative in ways that doppelgangers cannot match. While doppelgangers use subtly and deception, Illithids have power over the mind. You are likely familiar with magic spells that can influence others. Illithids have these kinds of powers naturally, compelling obedience with just a thought. They also... eat brains. Do not allow one to grip your head with its tentacles. Above all, however, they are most dangerous simply because they are extremely intelligent. They know how to use their powers to gain the most leverage."
Eligos pauses there, taking a large gulp of his tea.
