Fly back to the Pokémon League and head down the mountainside to investigate the dream that Hugh's sister had. Go down the stairway south of the two Veterans to find a Zoroark, the same one from your first visit to the area. It leads you back to the cave it had been guarding, and once inside, runs off down a tall stairway that connects to a ruined building.
N's Castle is the former base of Team Plasma that suddenly appeared two years ago. It was built in secret in the lands surrounding the Pokémon League, but fell into disrepair after the great battle, and eventually collapsed back into the ground.
Upon entering the ruined castle, you find N waiting at the bottom of the stairway. He asks that you lead him to the deepest chamber, a place that holds a special meaning to him. Only here will he face you in battle.
North of the entrance is N's old room. He tells you the sad tale of his childhood, then leaves the room in silence. Grab the Luxury Ball before following him.
A fallen column blocks the walkway, so climb down the rubble to the lower level. Pick up the Protein to the west before heading east. Before heading upstairs, be sure to grab TM50 (Overheat) to the southeast.
Go west until you reach the large crack in the floor, where N stops you. He says simply, "This is our destination... Go inside."
Enter the throne room and head north, where he catches up to you. He tells you about losing to a certain Trainer two years ago, and having to accept new ideas. He wants to know if you are a Trainer whose heart is strong enough to do that. He summons his friend ZekromB2/ReshiramW2 to his side, and asks if you are ready to battle. Despite having only one Pokémon, it can put up a serious fight. Defensively, you may want to use a high-level Ground-type Pokémon against Zekrom, or a high-level Rock-type Pokémon against Reshiram. Offensively, Ground moves like Earthquake and Ice moves like Ice Beam will be a big help.
Once you catch his dragon, N appears near Nimbasa's Ferris Wheel every Friday. After riding with him and catching Kyurem in the Giant Chasm, he returns to his castle for a once-per-month rematch with a team that changes with the seasons.
Tubeline Bridge is a steel bridge that connects Route 9 to Route 8. It is so sturdy that subway trains running beneath it will not cause it to budge an inch. A recent study reveals that it can support up to 4,934 people at once!
The woman on the east end of the bridge is very frustrated about all the loud noises. The noise level will increase every time you talk to her, from 70 decibels, to 80, 100, and finally 120 decibels. Talk to her when you are traveling with a Pokémon that has the Soundproof Ability, and she will notice something interesting about her surroundings.
Talk to the Battle Girl near the middle of the bridge. She was trying to outrun the trains, but got overheated. She gives you TM43 (Flame Charge), a low-power move that raises Speed, before running off again.
Route 8 is covered with marshes and water. Constant rain means that the route is always mucky, except in winter when the puddles mostly freeze over. To the north is the Moor of Icirrus, and to the south, Icirrus City.
The Moor of Icirrus is a large marsh that formed when water collected on the uneven ground. The area was once destroyed by an intense wildfire, and the Pokémon Rangers monitor the area to prevent the same from happening again. Fully exploring the area requires the use of Strength to move the boulder on the west side.
Go west from the entrance to find a hidden TinyMushroom in the line of trees. To the north, an old man tells you about the marsh's history and the fire that once raged here. Move the boulder into place to reach the southwest lake; defeat Pokémon Ranger Elaine to get a Lum Berry, and continue south to find TM84 (Poison Jab). Further north, a hidden Big Mushroom and a Green Shard lie on opposite sides of Fisherman Arnold. Head to the northeast area for a Heart Scale, then jump the ledge. A hidden Dawn Stone and a Rare Candy can be found in the middle of the southeast lake. South of that, Pokémon Ranger Parker gives up another Lum Berry, and a Full Heal sits nearby.
Icirrus City's wetlands occupy the area to the south, while the buildings are situated on higher, stable ground. The Pokémon Fan Club is located here, and you can win prizes for answering Aha's quizzes. Brycen, who served as the local Gym Leader two years ago, now works as an actor at PokéStar Studios.
The Gentleman in the Pokémon Center is interested in collecting any stones, gems, and minerals you might have, and is willing to pay double the normal price for them. He is the only person in the region who will buy Pearl Strings and Comet Shards.
Talk to the chairman and show him a well-trained Pokémon to get an item. Depending on the number of levels it gained since meeting you, he will hand over up to three different items. A Pokémon that has grown 25-49 levels will earn you an Exp. Share; 50-98 levels will get you a Cleanse Tag; and a Pokémon that's grown 99 levels will earn you a King's Rock.
The girl in the Fan Club will offer to check your Pokémon's mood. Choose a Pokémon to show her, and she will tell you how friendly it is toward you.
Aha's Pep Quiz
The home of Aha, Wye, and Ditoh is east of the former Gym. The mother, Wye, pulls you into the game the moment you step inside. The father, Aha, will ask you a question, while Wye gives hints to the answer. A correct answer will earn you an Antidote, while an incorrect one will get you a Parlyz Heal instead. You can take the quiz once per day.
The Shadows Reappear
Head east from the Pokémon Center and cross the bridge. When you reach the end of the path, the Shadow Triad suddenly appears. The Triad challenges you to three individual battles; a Single Battle, a Triple Battle, then a Rotation Battle. They also give you a chance to quit between battles. When the battles end, the Triad disappears without a word; however, they will reappear for a rematch once every season.
The first floor is pretty straightforward. Just follow the path to the stairs.
The second floor is littered with broken columns; these act as a bridge if you don't have a Pokémon with Strength. There's an Elixir under a column to the northeast, and an Ultra Ball on a broken column to the west. Don't miss the Red Shard hiding in the rubble!
The third floor is covered with one-way ramps. Jump to the south, then take the middle ramp west then north to reach a Shiny Stone. Grab the Protein in the northeast before taking the southernmost ramp west to the winding staircase.
Another straightforward floor. Climb the several stairways to reach the north side. To the east, a trio of items lie neatly in a row. These are the Adamant, Lustrous, and Griseous Orbs, which boost the powers of Dialga, Palkia, and Giratina. The legendary titans do not appear in Unova, but can still be found through othermeans.
The fifth floor is made up of four large circular paths around the central column. Head to the right to find a PP Max on the outer ring, then go left to reach TM02 (Dragon Claw) on the second ring from the center. Walk around the column to get a Max Revive, then go left to reach the stairs.
Another simple floor. Follow the path to find a Comet Shard, which can be sold to the Ore Collector in Icirrus for a whopping 60,000! Continue on to the stairs in the southwest.
Head on up through the narrow path, and the room begins to shake. Suddenly, the Dark StoneB2/Light StoneW2 begins to tremble inside your Bag. The stone floats in the air for a moment, slowly absorbing the aura from its surroundings before reawakening as ZekromB2/ReshiramW2. In a show of force, it sends out a shock wave of crackling electricityB2/blazing fireW2 as it descends to the ground.
First, exploit its weaknesses to quickly drop its health. Both dragons are vulnerable to Dragon- and Ground-type attacks; in addition, Zekrom fears Ice moves and Reshiram fears Rock moves. Next, wear it down gradually with Grass, Fire, or Electric moves. If you happen to defeat it, it will reappear once you defeat the Elite Four and Champion again.
After the battle, N appears and tells you to go to the Giant Chasm. According to his friend, Kyurem has returned! Once he leaves, be sure to track down that hidden Comet Shard. It is possible to Fly out of here, so take off for Lacunosa Town again and head east.
The Crater Forest has mostly recovered from the Plasma Frigate's impact, except for the sandy depression in the center. Enter the cave to the northeast and head to the back chamber to find Kyurem waiting for you. Save the game before starting the battle, as it will be much tougher to catch than the previous dragon. Dragon, Fighting, Rock, and Steel attacks will reduce its health the fastest, then weaken it further with Grass, Water, and Electric moves.
When the battle is over, Cheren and Bianca enter the cave. Cheren is impressed at the sight of Kyurem, while Bianca suggests showing your Pokédex to Professor Juniper. They run off, giving you the chance to grab the DNA Splicers that Kyurem dropped. When used, these let you fuse Kyurem with either Zekrom or Reshiram to create Black Kyurem or White Kyurem, respectively. The new Pokémon draws its level and other details from Kyurem. The next time you use the PC, you will receive some new Kyurem-themed wallpapers.