This is how Thunderwing drains Twilight's friends of their magic goes in Thunderwing's Revenge.
Thunderwing: Finally, the Element bearers right where I want them.
Rainbow Dash: You won't get away with this.
Pinkie Pie: We stopped you once we'll stop you again.
Rarity: We've dealt with stuff like this before.
Applejack: Let us go, you evil monster!
Fluttershy: And you leave our friend alone!
Starlight Glimmer: Yeah. What they said.
Trixie: Trixie agrees.
Thunderwing: I have already left Twilight's mind after she revived me.
[Thunderwing then drains them of their magic]
Thunderwing: You really think she'd do anything for them?
Ryvine Sparkle: If Ryan has magic to give, it will be yours. Soon there won't be a Pegasus, Earth Pony, or Unicorn who will be able to stand up against us.
Thunderwing: Us? Who said anything about us?
Ryvine Sparkle: You did. But. [shows Discord] Take him. I'm no longer of use to you.
Thunderwing: You've helped me grow strong, Ryvine, you've provided the means by which I can obtain all the Alicorn magic and now you are no longer of any use to me.
[Thunderwing then drains Ryvine Sparkle of his magic]
Ryvine Sparkle: What will the other villains say about this. Drain Discord's magic.
Thunderwing: My loyalty only belongs to my master, Unicron the true Chaos Bringer.
Ryvine Sparkle: Wait! Unicron is banished. Drain Discord's magic and restore mine.
Thunderwing: You are worthless as anyone.
Ryvine Sparkle: Look. I know you need a deal. You let me go with my magic and I'll give you Discord's bad clone's magic in exchange. I'm with the villains not the heroes.
Thunderwing: You're wasting my time. [grabs Ryvine and throws him away from him]
Ryvine Sparkle: YOU HAVEN'T SEEN THE LAST OF MEEEEE!!!!!
Thunderwing: Well. I guess I'll take Discord's magic instead of Ryvine's.
[He grabs Discord and drains his magic]
Thunderwing: There. Much better. [to Discord] Now I know why Fluttershy reformed you, fake Lord of Chaos. You know nothing of chaos unlike my master, Unicron the Destroyer. Unicron the true Chaos Bringer. Unicron the true Lord of Chaos. Unicron is and always will be the real Chaos Bringer and the Lord of Chaos. You will always be nothing but an insect who knows nothing of true chaos.
Discord: The true meaning of chaos was something I weilded long ago.