Mistique's only answer to Noah's foreseeably favorable reaction was an enigmatic smirk, before sauntering out of the chamber to meet with the others. She had decided to keep the 'costume', apparently.
Nefertiti:
The mentioning of this word Halloween is unknown to her for she was born at a time way before it was celebrated.
Looking at them in a daze expression but still she listened to see what all she could grasp.
Grey:
As Sal took a seat nearby, Grey beamed. "We're playing Halloween today! You dress up and get candy!"
Now appearing in the blue-skinned, scarlet-haired, white-gowned form of Mystique from X-Men, Mistral explained to Nefertiti in a melding of the character's voice and her own,
"Halloween is a holiday celebrated by costuming oneself, often as fictional characters as Grey and I have. It originated from a celebration of the dead known as All Hallow's Eve, or 'Toussaint,' en français. In the Western world, it has become a day for revelry of a light macabre theme." She regarded the demi-goddess with pupil-less yellow eyes and asked,
"I have seen artwork from your era of holy men and women in the animalier likenesses of the gods. Were such costumes used in divine rites, or otherwise?"
Fate:
Fate looked up from her book upon seeing Mistral's illusion and pondered something. "That's quite an impressive illusion, but then again with what I've seen you capable of this must be nothing. I wonder, do you think that you could teach me some of your magic. I'm still such a novice, but perhaps with a touch of your kind of magic I could improve my level."
Mistique smiled and nodded once.
"You are inquisitive, Madame Fate. I appreciate this, as I have similar inclinations. Oui, I could teach things that would be of use to you. I doubtless have things to learn from you, as well."
When Michael provided a rough location for his Haven on the satellite map, Mistral took the slate back and studied it briefly, zooming in and panning around the surrounding area. Having gotten what she needed, she dismissed the slate into thin air and then twirled a wrist in a circular gesture while speaking a syllable of power. A round portal with supernal vapor boiling off its edges opened against an amethyst wall, through which could be seen a dingy brick wall in some other place. Mistique got Michael's attention, then explained,
"This Porte will take you to an alley one block's distance from your haven. It is only visible and traversable to those of us present, as well as to those brought through by our intent. It can be opened and closed, as so." She performed a gesture like pushing closed a door and spoke the phrase,
"Seal the way." The portal closed at the command. She then performed a gesture like turning a knob and pulling a door open and spoke the phrase,
"Open the path." The portal reopened on command.
Mistique turned to Michael with a hand resting on a blue-skinned hip, then said,
"The Porte shall remain for one day. Will you go solo, or would you have assistance?"