Having spent a cantrip to confirm that Halish should be in his right mind, Anthony wakes him up.

"Back with us, friend? Sorry for not letting you sleep, but I had to improve the chances that my magic will work, and now we plan to tackle this shadow portal real soon. Can you give us advice or any other valuable information you might have overheard or otherwise discovered? I plan to leave these three youngsters in your care. One of them is free from domination and two others are not. Cast Resurgence on them while they are asleep and they'll come to their senses, if maybe with more than one try."

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With those rolls, I believe a single Resurgence is enough to free him of the enchantment.

Also, any luck with monocling the portal? Anthony can even do that himself now that it is the morning.