This is how Unicron and Thunderwing's defeat goes in My Little Pony Transformers Prime: The Return of Harmony.
[Unicron is sitting on a throne with Thunderwing at his side. Thunderwing hands Unicron a glass of Dark Energon and Unicron takes it]
Unicron: Chaos is a wonderful thing.
[Unicron suddenly hears the sound of an approaching engine and turns to see Optimus and the Autobots, in vehicle mode, coming towards him]
[The Autobots transform to robot mode and the ponies, including Twilight, stand before them]
Rainbow Dash: Not as wonderful as Friendship!
Fluttershy: You two have caused enough trouble.
Rarity: That's right.
Pinkie Pie: Play-time is over for you two.
Applejack: And look whose back in the lead.
Twilight Sparkle: Yeah.
Thunderwing: Ugh, this again.
[Unicron drinks his Dark Energon drink and throws the glass and it stops mid-flight and it falls to the ground]
Twilight Sparkle: That's right. You can't control me again.
Thunderwing: Come now, Twilight, don't be foolish.
[Thunderwing's hand glows purple and Twilight starts moving towards him]
Thunderwing: I am your only friend.
[Thunderwing floats Twilight up to him]
Thunderwing: Will you ever learn?
[Thunderwing reaches for the Element of Magic, when he is suddenly blasted from behind by Optimus]