It hits him like a splash of cold water, and he sends back a clear and emphasized message.

He is coming to take her home.

Vincent opens up a comm channel to Avengers Mansion, and layers a spell on top of it to reach anyone there who might not be listening to a speaker.

"Loki has my sister and he's taking her to Asgard. I am going there. Anyone hearing this can either help or stay out of my way. I'll be returning to the mansion shortly to collect any volunteers."

He rises from the center of the spellwork and nods sharply to Kristoff. "There's no time to lose."