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Your next goal is to find your way to the Temple of the Ancients. You don't start out knowing where it is, and if you happen to find your way there, you'll notice that you can't get in. Now that you have the Tiny Bronco, the game gets a bit less linear. You can, and should, explore stuff! Time to head to the firm land again. Just about every random NPC you find will babble something about Sephiroth's whereabouts anyway.

[edit] Things to do

• If you feel you need to level up a bit now is the perfect time to visit the Mideel Area.
• You can do Wutai sidequests. Have at least average party level 32 to do the first quest, and have Yuffie at that same level if you also intend to do the second Wutai quest.
• You can try your luck at Fort Condor. This is not necessary though, and you gain no real benefits from this.
• If you didn't do this earlier, grab two fairly essential enemy skills: Go to Junon and find a Zemzelett, manipulate it to get the White Wind. Go back to the Midgar Zolom guarding the swamps near the chocobo farm. It's a level 23 creature, so it should be pretty simple to bash by now, and it can teach you the Beta Enemy Skill.
• If you want to learn or see Aeris' Level 4 limit break, this is about your only chance. See Aeris' limit breaks for more details.

[edit] The Keystone

In Bone Village (a village on the northern continent, a big dinosaur skeleton sticking out of the woods), the guys working there have seen Sephiroth looking for the "Keystone," except that apparently some rich guy has it. The guy at the weapon shop on the peninsula south of Golden Saucer and east of Gongaga was the previous owner - and he tells you that the stone was sold to Dio, owner of the Gold Saucer.

Head back to Gold Saucer to retrieve the Keystone. Dio was the Manly Man and logically keeps all of this stuff in the only location you didn't scour thoroughly on your first visit to Gold Saucer - the Battle Square. You'll find out, of course, that Dio has a showroom full of really weird things. Really big alarm clocks, genuine Klein bottles presumably for sale, and the Keystone.

Dio shows up, and won't let Cloud borrow the Keystone unless he fights in the arena. Basically, this is one-on-one fighting against all sorts of weird critters, with a random handicap between the fights. For details, see the Battle Square guide, though you won't need the guide much in this fight - after all, there's only one possible prize this time. The goal here is to survive at least one fight. Just keep defeating monsters as long as you can stand up. If you get wiped out in the first fight, Dio will let you try again.

After a successful fight, Dio gives you the stone. When you go to leave, you find that the cable car is busted. Luckily, Cait Sith knows the hotel owner. There's a brief cutscene where Cloud and the rest try to recap exactly what you're trying to accomplish next and what strange mystical things we've learned of the Cetra.

[edit] The date

In the middle of the night, one of your party members shows up. Which party member depends a lot on who you've been treating best over the course of the game. If you've constantly worried primarily about Aeris, she shows up; if Tifa, she shows up. With a little bit of trickery, it's possible that Yuffie or Barret will show up, both of which have amusing dialogue in the following scenes.

Now, it's time for a little bit of romantic and silly fun. The first stop is the Event Square - here, you'll end up acting in a play. It really doesn't matter what dialogue choices you make - just pick the ones that seem like good ideas at the time. The results are usually exactly what you expect them to be.

Next up is Round Square. If you didn't try this before, you can make Cloud look in different directions with the movement buttons. Your companion will tell a lot of interesting things here.

The date ends when you see Cait Sith making off with the Keystone. After a little bit of chasing him around the place, a few things become apparent: he just handed the Keystone to the Turks and he has Marlene as a hostage. After a bit of dialogue, you end up back in your hotel room. Be sure to check the wardrobe for an Elixir.