The Cat and The Keystone
East of Gongaga Village is a Weapon Seller who lives in a house by himself. He can tell you a little about the Temple of the Ancients, but not much. The most important information he has is the fact that you need a Keystone to enter the Temple of Ancients. Unfortunately, he just sold the Keystone to Dio, the owner of the Gold Saucer.
Head for North Corel and ride the Ropeway to the Gold Saucer. This time around you'll want to drop the 30,000 Gil for a life time pass to the park. You'll return here a lot if you decide to breed and race Chocobos.
Go to the Battle Arena, check out Dio's show room and you'll find the Keystone, which is on display. When Dio shows up, Cloud asks to borrow the Keystone; however, Dio isn't going for it. There is another option: if you're willing to fight in the Battle Arena, Dio will give you the Keystone.
Tip:
It doesn't matter how far you get in the Battle Arena, you just need to try. However, if you can defeat all eight opponents in the Battle Arena, you'll receive a Protect Vest and Choco Feather in addition to the Keystone.
After the battle Dio hands over the Keystone so you can be on your way. But wouldn't you know it, the Team is out of order. It looks like you'll be spending the night. Fortunately, Cait Sith has connections and can get you into the Ghost Hotel.
In the middle of the night, Aeris comes and asks you to take her on a date. This is the perfect opportunity to tour the Gold Saucer and enjoy the rides for free. But first, you get invited to take part in the Gold Saucer's stage show.
Note:
Aeris may not come to your room if you're treating her poorly. If this is the case, you may get a visit from another party member.
Note:
Play along with the show if you'd like, but it's far more fun to mess it up
After takeing part in the show, it's time to venture to the Gondola ride. Look out the window when Aeris looks out to watch some really cool scenes.
After the ride, Cloud and Aeris bumb into Cait Sith, who's attempting to steal the Keystone. Chase him to the arcade and then to the Chocobo Racing forum. The bad news is that you can't stop him before him gives the Keystone to Tseng of the Turks. So that's it! Cait Sith is the spy!
It looks like Cait Sith is staying with you regardless of you wishes. FOrtunately, he knows wehre the Temple of Ancients is, so hop in the Tiny Bronco and head out to sea.
Note:
Check Cloud's dresser in the hotel and you'll receive in Elixir.