Thor: Why have you done this?
Loki: To prove to Father that I am a worthy son! When he wakes, I will have saved his life, I will have destroyed that race of monsters, and I will be [bad word] heir to the throne!
Thor: You can’t kill an entire race!
Loki: Why not? *sarcastic laugh* And what is this new-found love for the Frost Giants? You could have killed them all with your bare hands!
Thor: I’ve changed.
Loki: So have I.

Loki hits Thor.

Loki: Now fight me.

Loki lashes out at Thor again.

Loki: I never wanted the throne! I only ever wanted to be your equal.
Thor: I will not fight you, brother!
Loki: I’m not your brother. I never was.
Thor: Loki, this is madness!
Loki: Is it madness? Is it?! Is [bad word] on, what happened to you on Earth that turned you so soft?! Don’t tell me it was that woman?!

look registers on Thor’s face.

Loki: Oh, it was! Or maybe, when we’re finished here, I’ll pay her a visit myself!