Legend of the six (Book 1)

The Past

(The mist transport Elsa to her memories in the form of ice and snow)

Everyone: Wow
Elsa: I finally get to know.

(She walks past memories of her and her sister as kids, her singing let it go, the Duke of Weselton dancing around her, and even when Anna met Hans. She smashed the ice statue of him.)

Hans: Why did she? 
Hans gets shocked. Everyone else laughed

(Elsa reaches her parents' memories. Iduna tells Agnarr about her past. Elsa sees her parents as kids. Then she sees a memory of her mother hiding in a cart with her father knocked out. Elsa hears her mother talking to another Northuldra.)

ELSA: Hiccup and Sabrina’s mother.

Hiccup and Sabrina look at their mother.

YOUNG IDUNA: Did I do the right thing? I mean, I saved my enemy.

YOUNG VALKA: Yes you did. But for now, we need to leave or will all be trapped in here.

ELSA (whispers): Our mothers were close friends.

Elsa, Sabrina and Hiccup look at each other.
Sabrina: And so are we.

(Elsa hears her Grandfather next.)

SOLDER #1: King Runeard, I’m sorry. I don’t understand.

ELSA (whispers): Grandfather?

RUNEARD: We bring Arendelle’s full guard. 

SOLDER #1: But they have given us no reason not to trust them.

RUNEARD: The Northuldra follow magic. Which means we can never trust them.

ELSA: Grandfather?

RUNEARD: Magic makes people feel too powerful. Too entitled. It makes them think they can defy the will of a king.

Elsa and Sabrina: He's scared.

ELSA: That is not what magic does. That’s just your fear. Fear is what can’t be trusted.

Jack: True. We have the body of fear and he can't be trusted.
Dagur: What?

(King Runeard and his soldier walk through a wall, Elsa uses her powers to make an entrance and follows them.)

RUNEARD: You see, the dam will weaken their lands, so they will have to turn to me.

(Elsa keeps following them while hearing her mother’s lullaby with the warning. She keeps going until she reaches a chiff and listens to what Runeard says.)

RUNEARD: They will come in celebration. And then, we will know their size and strength. 

(Elsa looks back at the entrance then back at the memory.)

RUNEARD: As you have welcomed us, we welcome you… our neighbors, our friends.

Everyone got really uncomfortable.

ELSA: No turning back.

(She takes a deep breath and jumps down to the bottom. She starts feeling cold, she looks at her hands, they are turning to ice. She looks around and then hears the memory of the day the forest fell.)

Jack: Oh no.
Anna: She's turning to ice to save the forest.

NORTHULDRA LEADER: King Runeard, the dam isn’t strengthening our waters. It’s hurting the Forest. It’s cutting off the North…