Final Fantasy X-2

Get Besaid Key and get the search sphere.

Collect All 10 Crimson Spheres to unlock this Dungeon.

First you'll have to meet with Maechen at Guadosalam in Chapter 3. You'll find him when you meet up with Logos and Ormi in the same area. Next you have to get the "whistling" scene with Yuna at the end of Chapter 3. When you're alone in the Farplane, move Yuna around and continually press the X button. You'll hear whistling. That means you have activated the event. Next thing you have to do is get an Episode Complete in Luca during Chapter 5. All you have to do there is visit the location where Tidus taught Yuna how to whistle. Next, get an Episode Complete in Besaid. Finally, once you have defeated Shuyin at the end of the game, keep tapping the X button to get your just rewards.

Send a level 5 chocobo to Mihen Road.

In Chapter 5, go into the room with the lift and go to the right. You should see the Kinderguardians there and a new portal by them.

To use each character's special Dresspheres, you must activate all the Dresspheres on your Result Plate (all lines in the plate should be glowing in blue). If activated, the "R1 Special Dress Change" message will flash. To change, press R1 and Action. The only difference is that the Special Dressphere will control the other character, and the character using the special Dressphere will be the only one who will receive the experience.