Loki knows they are coming. There is no way they cannot be. And when he steps off the train, well hidden by his illusions, he sees Thor streak overhead and feels the ground shake as he lands. He moves swiftly through the park to an open field and, with Wanda, Natasha, and Steve approaching from one side, Thor from another, and Tony in the sky, he drops his illusions, except for his sceptre, and raises his face to the sky.
"Heimdal! I, Loki Odinson, of...Midgard, demand an audience with the All-Father!" Green energy crackles around him and his voice is rough and harsh, "I have something that might interest him."
Thor twirls Mjolnir.
Wanda shouts, "No! That will kill him- he's one of us, remember?" Mjolnir stops abruptly.
"What are our orders, Wanda?" Tony asks from the sky.
"I will engage him first." She strides towards Loki, her face grim, "Loki, stop this!"
"Stay back! You do not know what I can do- or what I am willing to do." He is shouting, still, as though this is part performance, "Come no closer, any of you! I will kill you if you try to stop me! Oh yes, even you, dear Sister. Even you." But she does not break stride. Her wisps become visible, floating from her fingertips, crackling at the end of her hair. When she is close enough that he can drop his voice, he does, "Please, Wanda. Don't make me do this." But she does not stop.
There is a green ball of energy in his hands in a moment and he throws it at her. Steve, following behind her, is ready to push her out of the way when it impacts a foot in front of her against barrier of red light that did not exist a moment before. The green curls outward like smoke, dissolving as it cracks along red edges. Natasha circles, watching. The Scarlet Witch against Loki. Magic and wisps. Nothing she has ever seen before.
Wanda gathers a ball of her own red and tosses it to him. He deflects it into the ground and lashes back at her. She uses her wisps to catch what he has thrown her and to whip it back at him even faster. He is amazed that this is even possible and hesitates only a fraction of a second, but it is enough that he cannot react fast enough. The whip catches his side and knocks him off his feet, throwing him away from Natasha. He winces as he tries to stand and stumbles. It is enough time for a wisp of red to connect with his temple. This one, though, does not move him. He is rooted to the spot.
It takes every ounce of her concentration to keep moving towards Loki while her wisp holds him captive. She pushes it farther and begins to try to work her way into his mind. He resists at first, but then caves, dropping all barriers and letting her fully wrap herself into his memories.
From Natasha's point of view, it is over, even though she knows there is a different battle being fought. Steve stands back, watching. Tony lands beside Thor. Natasha joins them.
"So...what's she doing to Reindeer Games?"
"I do not know, Metal Man. But he appears to be allowing it."
"Yeah. And that's what I don't like. What if he hurts her?"
"Can my shield sever the connection or would the...whatever she has...just go right through it?"
Thor shrugs, "I do not know. But we ought to stay close, just in case."
Clint's voice comes over their earpieces, "I'm assuming I'm still supposed to hold this shot?"
"Yeah, hold it. At least until we figure out who is doing what to who."
"Roger, Nat."
They fan out and cautiously step closer.