Yu-Gi-Oh!, Season 4: Waking with Dragons

Joey:
Please, Mai, tell me this is all a joke! You're on our side, remember?!

Tristan:
Great. Mai totally sold us out!

Tea:
No! Mai would never do that! Tell him. You're still our friend, right?

Yami-Yugi:
Time to explain yourself.

Mai:
I was never a part of your little playgroup. And now I'm gonna break you apart one-by-one. And Wheeler… I'm starting with you!

Joey:
Fine!

Mai:
It's payback time, and it all starts, now! And to think, I was once pathetic enough to call you my friend. But now I know the truth! You were holding me back from achieving true power! So say hello to my real friend… THE SEAL OF ORICHALCOS! This card's done for me than you losers ever could! [activates the card, sealing herself and Joey in it]

Yami-Yugi:
No! Not this!

Mai:
[chuckles sinisterly] If you're scared now, just wait till you lose.

Joey:
Wake up, Mai! This thing's nothing but bad news! It's messing off your head, big time! Don't you remember everything we've been through together? Just ditch that freaky card, and things can be that way they use to be!