When you reach the sandbar near Parasol Lady Laura, take the western path first. The man further down the beach is a treasure hunter, and will give you some of his extra items. Speak to him every day to get one of the five kinds of Flute, which can be sold to the billionaire in Undella Town for a high price.
Cobalion is waiting
Farther north, the beach gives way to the forested high ground. Climb the stairway and approach the cuttable trees to find Cobalion standing in the clearing beyond. Now's your chance to catch it! Start off with Fire-, Fighting-, or Ground-type attacks to wear it down fast, then follow up with Normal, Grass, Ice, or Steel moves to weaken it further. Avoid using Dark-type attacks, as its Justified Ability raises its Attack when it is damaged by those moves. If you happen to defeat it, Cobalion will reappear after entering the Hall of Fame at level 65. So you may want to consider capturing Cobalion at a later time if you don't plan on adding it to your team right away.
Enter the town and head south, and Professor Juniper and Bianca will call out to you. The professor leads you both to a house on the north side of town. She asks the old woman here to tell the legend of the Giant Chasm. The old woman claims that the area was formed when a meteorite that contained a Pokémon crashed into the planet. At night, that Pokémon would attack humans and Pokémon alike, and always appeared with a frigid wind that could freeze someone to the bone. Juniper believes that the walls built around the town may have earned it the name Lacunosa, as lacunosus clouds resemble a fence.
Head west from the Pokémon Center to meet up with Hugh again. He's here because he heard rumors of Team Plasma in the city. Suddenly, Zinzolin and a Grunt appear, After hearing Team Plasma's plans, your rival snaps and asks for your help in battle. Combine your strength to take out the two criminals.
Visit the easternmost house, and talk to the woman inside. She heals your Pokémon back to full health. There is no Pokémon Center nearby, so visit her when your Pokémon need a break.
Stonewall's Winning Streak
Head up over the bridge, and a Gentleman suddenly stops you. He is trying to set a record for most consecutive wins, and only needs one more to reach 1,000. Even though you defeat him, he can't wait to begin again.
Enter the room under the west side of the bridge to find a woman practicing her singing. She chases you out, and when that happens, talk to the girl directly above on the bridge. For clearing up the mystery of the voice she heard, she gives you five Sitrus Berries as thanks.
Route 11 is a short, paved road that passes over a river flowing out from a waterfall. The gate on the west side leads to Opelucid City, home of the next Gym.
When you reach the west side of Route 11, the legendary Virizion suddenly leaps down from the cliff. It seems that it, like Cobalion, was also waiting for you. Start off with Fire-, Ice-, or Flying-type attacks to wear it down fast, then follow up with Water-, Rock-, or Ground-type moves to weaken it further. Avoid using Dark-type attacks, as its Justified Ability raises its Attack when it is damaged by those moves. If you happen to defeat it, Virizion will reappear after entering the Hall of Fame at level 65. So you may want to consider capturing Virizion at a later time if you don't plan on adding it to your team right away.