This is how Starlight, Trixie, Thorax, and Discord warn Twilight about Thunderwing goes in Transformers Prime: Attack of the Changelings and Thunderwing.
Starlight Glimmer: Twilight!
Trixie: We need to warn you about something urgent!
Thorax: Some Cybertronian giant wants to destroy the Elements.
Discord: Along with their weilders.
Twilight Sparkle: What?! What's his name?
Thorax: His name is Thunderwing and he's a servant of Unicron. [shows image of Thunderwing and plays what he said when he awoke].
Thunderwing: (voice) Death to the Elements of Harmony!
Twilight Sparkle: What?! Optimus said he was done with.
Trixie: Apparently Unicron rebuilt him and sent him to destroy the Elements of Harmony.