Team Anna!
"You go first," Anna told Isaac, since he was the one with the super senses. He could make sure they weren't heading right into a pit of demons or something, and though she anticipated a straight shot to the portal - which was bright, she could see it crackling from here, and she didn't want to even imagine where it would lead - she at least knew enough by now, about this place, to say that nothing was ever certain. Things could be waiting to pop out and eat them. "With Ariel." Her ginger friend was a scrappy fighter! Much like Anna herself.
As for Loki and Elsa, she made an Anna Sandwich between them, since they could be considered the heavy hitters on the team - what with their magic and all. "You two stay with me? Please?" Like right here, she was good with that. They could be the offense, officially.
And she just felt better, being sandwiched. The only worry was drawing her sword and not slashing either of them in her enthusiasm.