ZAAAACKKK!!!
And poor, poor Cloud. ::weep::
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EDIT: Here's a rough translation of the ending from the Advent Children Crisis Core Forums (just follow the instructions to access the Spoiler Forum).
Cloud: "... Zack."
Zack: "My part till now..."
Cloud: "Your part?"
Zack: "That's right... you are..."
Cloud: "... you are?"
Zack: "Live. You're the evidence that I lived. My pride and dreams... have them all."
Cloud: "... I'm the evidence that you lived..."
- Scream -
Zack [flashback]: "Grasp your dreams! If you want to be a hero, you'll have to grasp for your dreams."
Cloud: "Thanks... I won't forget. ... Good night, Zack."
Zack: "That kid, a new sky that won't scare him. As I thought, it feels fulfilling. Those wings, give them to me too. Because it kinda feels... nice. If you meet Aerith, I'll be counting on you. Hey... Now I've become a hero, right?"
- After Ayaka's "Why" and the credits -
Cloud: "I'm Cloud. Soldier, first class."
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But make sure to watch the very last bit, though. *_*
Now I absolutely have to work on Feral-verse, if only to make myself feel better. ::massive wibble::