It leads to a homey, roomy tree, lit by fairylights in easily-covered locations. It doesn't have any airholes. There are books, not covered by wood right at this moment, and a little kitchenette and a basin of water and a bed and a sewing room and lots of drawings decorating its interior surfaces.
Once out, he changes out one of his powers. Charging up takes longer than it used to, but in a few minutes he can sense every person in a long enough range that he can see Fairyland's flatness directly. He chooses the largest collection, and warps to just above them.
A fairy notices him and starts flying up to see what's going on.
For this to work, he's probably going to have to play the villain. "Send me your sorcerers, if you think they can face me." Green light flashes across the sky. Presentation.
"Yes. I am Eidolon. I am here for a fight, and know exactly what I'm gambling."
"Or...whoever you call on when threatened.
You know what, I'm here to forcibly collect all your names. Please raise the alarm and have people try to stop me."
"I am Eidolon! Face me if you want to keep your names!"
Is this what it's like for his opponents all the time?
The court up the mountain has homes dug into the mountain, perched up trees, in mounds of earth on the slope, and in a few gigantic flowers. The presumable home of the court's master is a fancy building with lots of glass and shells; someone peeps out of the window, then disappears. A minute later fairies of various shapes and sizes and colors fly out of the fancy house and address others in the court. Apparently getting a court ready for unexpected challenges like this takes a while.
In a few minutes he'll be fully prepared for whatever they throw at him.
The cold isn't going to be literally everywhere; he considers locations to teleport to until one of them doesn't involve being frozen. With any luck he'll be in blasting distance of his opponents.
This is enough of a move against him that his precognition tells him their path, but that doesn't make it a threat. He appears in the middle of the buzzing and strikes at them with telekinesis. One fairy gets a small piece of mortal fruit blasted toward their face, stopping before it arrives. "I'm looking for people who can fight me. Where are the sorcerers?"
The inches disappear, and the pomegranate seed starts pressing itself through the fairy's mouth.
"Where are my opponents?"
"Tell me, and then you're free. If you're not a sorcerer."
The problem with these parahuman powers is that they tend not to work on things inside other people's bodies. He forces her mouth open with yet more telekinesis, and flies the seed down her throat until his power is no longer able to affect it.
"Tell me where my opponents are, and if you are not a sorcerer you're free."