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You are reporting to Chatot and the other guild members that, despite your greatest efforts, you could not protect the Time Gear. Chatot says that it's quite all right, but you and your partner still feel down all the same. The rest of the guild is also upset, since they missed their only chance to get the drop on Grovyle. However Dusknoir informs them that's there's a third member of the lake trio, Azelf , and that he's likely to be guarding a time gear in a lake that's not where it's supposed to be.
As the guild try to hash out where the lake is likely to be, Dusknoir remembers the crystal Bidoof grabbed at Crystal Cave and asks to borrow it for your Dimensional Scream. Bidoof refuses, but Dusknoir explains that it's important. Everyone else is puzzled as Bidoof hands over the crystal, and you touch it. You don't feel anything at first, but then...
The dizziness is coming back. You moan in displeasure. Despite you going to find out something, it's still quite uncomfortable.
Then you see it. An unknown Pokémon is shown being threatened by Grovyle. Grovyle is then seen knocking down the Pokémon and taking the Time Gear.
After a while, your partner asks if you saw something. You explain what you saw to the guild, causing them to get excited until Chimecho asks whether it was the past or future you saw. You brood, wondering if that was the past or the future. They all get upset, Chatot wondering if that was the past. Dusknoir diffuses the issue by stating that, because Azelf was never mentioned prior to that moment, it's likely the vision was from the future. After waking up Wigglytuff (who fell asleep at the worst possible time), everyone decides to head off to where Bidoof, Dugtrio and Sunflora went--Crystal Cave!
All ready now!
After a few preparations, it's time to go. Be warned that the guild isn't really going with you, or you just made it first.
A very pretty cave with many Ground types. Hence its name, there are many crystals around. It isn't too tough, as you can defeat this very easily.
After getting through the dungeon, you will see three large crystals. After a bit of confusion, the Dimensional Scream triggers, where some voices say you will have to change the color of all three crystals (by pressing A on them) to make the door open. Change it to Blue. After that, head over to Crystal Crossing!
An advanced Crystal Cave with no specific type. Despite it being harder than Crystal Cave, it still isn't too difficult. Battle your way through all the wild Pokémon and make it to Crystal Lake!
Once you get there, you'll see you've arrived right in the middle of your first vision. The unknown Pokémon earlier is revealed to be Azelf, who looks quite weak and tired. Hence, it is not your boss...since Grovyle just came right now!
Grovyle says his usual "I'm not here for you" line, but before he can move toward the Time Gear, Azelf, who was warned that Grovyle would show up and anticipating a scenario where he'd lose, puts a barrier of crystals around the lake. You and your partner stop him from finishing of Azelf to remove the crystals. He scoffs at you interfering, and then starts a battle with you, thus being your boss.
A very hard battle ensues. He has 200+ HP, not to mention his powerful moves. However it is possible to win by using SmokeScreen to make a Whiffer status, and then, if you are a Fire type or know any Fire moves, hit with Flamethrower or another powerful Fire type move. However, even if you win, Grovyle knocks your team back then tries to take your partner down, but Dusknoir protects you again. However, Grovyle escapes, and the rest of the guild carries your team back to the guild as Dusknoir chases after him. This marks the beginning of Chapter 13!