This is how Thunderwing vs. Tirek goes in The Return of Unicron.
[Tirek finishes absorbing the Alicorn magic out of Princess Celestia, Princess Luna, Princess Cadance, and Twilight Sparkle and prepares to leave when Thunderwing flies towards him and stops in mid-air.]
Tirek: Well, well, look who decided to show up.
Thunderwing: I'm not here for any of your games, Tirek.
Tirek: Yeah, whatever.
Thunderwing: I'm here for what is rightfully Unicron's: Equestrian Magic!
Tirek: So what? You're a Cybertronian. You don't know a thing or two what Equestrian Magic can do.
Thunderwing: Spare me your lectures! You know nothing of power!
Thunderwing: Do you know what real power is?
Tirek: Get to the point.
Thunderwing: True power...is simple determination! Making the impossible possible through sheer FORCE OF WILL!
[Thunderwing releases a wave of force that makes Tirek flinch]
Thunderwing: I have risked everything in pursuit of this power! I have given myself over to it, body and spark! Now witness...the power of one who has SACRIFICED EVERYTHING!
Tirek: Ha! If you believe that... then you're a bigger fool than I thought! Witness the power of one who risks NOTHING!
Thunderwing: SO BE IT!
[Thunderwing transports everyone to a gladiator arena and Thunderwing and Tirek battle each other in the pit as Twilight and her friends, Princess Celestia, Princess Luna, Princess Cadance, and the Autobots watch on the stadium.]
Tirek: Enough magic tricks! Time for some hardware!
[Tirek fires four blasts of magic at Thunderwing, but Thunderwing dodges them all]
Twilight Sparkle: That's weird. The bad guys are fighting each other.
Optimus Prime: It's because they are fighting for leadership.
[Thunderwing then flies to Tirek and punches him to a wall]
Thunderwing: Now this is fire power!
[Thunderwing shoots Tirek]
Tirek: [screams in pain]
Tirek: You think that's all you've got?
Tirek: Well, what do you propose?
Thunderwing: How about we put it this way, winner gets the Equestrian Magic.
Tirek: Very well.
Thunderwing: Bring it on!
[Tirek creats a big ball filled with Equestrian Magic he absorbed and throws it into the sky]
Tirek: Try catching that.
[Thunderwing and Tirek continue their battle]
Tirek: You're not going to win that easily.
[Tirek fires at Thunderwing, but Thunderwing dodges it.]
Thunderwing: You'll have to do better than that.
Tirek: Bravo, Thunderwing. Your performance is so convincing, I almost want to applaud. [laughs]
Thunderwing: Oh, how generous of you. In turn, let me give you a big hand.
[Thunderwing's right arm grows bigger and heads towards Tirek]
[Thunderwing's arm punches Tirek into a wall and retracts back towards Thunderwing and shrinks back to its original size]
Thunderwing: You know it's pretty amazing when you think about it. With the power I already absorbed, I can increase the mass of my body at will. And soon I will multiply that power a hundred fold.
Tirek: That's not true.
Thunderwing: I know it is.
Tirek: Then bring it on, you over-sized tin-can!
Thunderwing: Let's blow the roof off this place.
[Thunderwing unfurls his wings and flies into the sky]
Thunderwing: What's wrong, centaur? Can't fly without wings?
Tirek: I may not be able to fly, but I do have magic.
Thunderwing: So what? I have Dark Energon and I'm going to obtain all that Equestrian Magic when I defeat you.
Tirek: Well, if you want it, come and get it. [beckons]
Thunderwing: Oh I will. [flies toward Tirek at maximum speed]
Tirek: Come on. A little closer.
[Thunderwing grabs Tirek and mercilessly assaults him and throws him to the ground and shoots him and ceases fire]
Thunderwing: Thus endeth the reign of Tirek.
Tirek: How can this be... am I... to be defeated... by Thunderwing?
Thunderwing: You are.
[Thunderwing and Tirek
Twilight Sparkle: Who won?
Starlight Glimmer: I see something.
[Thunderwing is seen floating in the sky and Tirek is nowhere to be seen.]
Thunderwing: You see, Tirek, when you risk nothing in the pursuit of power, you could wind up with nothing. That's why I risk anything.
[Thunderwing then grabs the big ball of Equestrian magic and flies away]