Quote Originally Posted by Craig
Yeah, he comes back in the good and perfect endings.

There are certain points in the game where you need to tap X to whistle, but I can't remember where they are.

If you don't do the whistling he doesn't come back, check GameFAQs or something.
(SPOILER)You mean in the Farplane Abyss. In chapter...3 I believe. Fall into the hole in Djose Temple, cause of the impact cause Ixion blew up. You see all this light, Yuna thinks she's in heaven or something, then she thinks she hears Tidus, but is actually Shuyin (the dude in the sphere the person was talking about with the cage and stuff. aka Lenne's lover) Then after the coversation about Shuyin wanting to get revenge on the world by destroying it, he leaves and you have to keep moving Yuna around until the light goes out, and then she screams and then she's like "I'm all alone" and then you hear Tidus whistle, and then you press X and then he'll pop up as a ghost going up some stairs, and then he'll disappear, and then he'll whistle again, so you press X again, and then he'll be going up some more stairs, and then he'll disappear again, and then he whistles one last time, and then you press X again, and he'll go up the stairs and then Yuna will go up the stairs automaticaly, and then you'll end up in Bevelle.

Whoosh, that was large.