This is how Twilight vs. Midnight goes in A Canterlot Wedding.
[We see Thunderwing and Midnight standing in front of Celestia]
Thunderwing: Give up, Celestia! Canterlot is ours now!
Princess Celestia: Never.
Thunderwing: And do you know why? Because you didn't believe your student when she told you that the fake Cadance was evil.
[Princess Celestia sees a hologram of Twilight]
Princess Celestia: Twilight.
[Thunderwing sees the hologram of Twilight]
Thunderwing: Midnight, deal with the Unicorn.
[Midnight goes to deal with Twilight]
[Twilight sees him]
Midnight: Celestia taught you well. But you still have much to learn.
Twilight Sparkle: That's what you think.
[They start fighting]