On the 6F of the Pokémon Tower, you’ll witness a ghost of some sort just as you’re about to approach the stairs to the 7F. This requires the Silph Scope that is obtained after defeating Giovanni in the Team Rocket HQ. Using the Silph Scope, this will reveal the identity of Cubone’s deceased mother. Marowak is on Level 30. Because it inhabits the spirit of the ghost, it cannot be captured regardless of any ball you throw, so you have no choice but to defeat it. After you defeat it, its soul will depart to the afterlife and you can rescue Mr. Fuji on the 7F. ... https://www.youtube.com/watch?v=fHwCpR_9w2w
Go to Klubba’s Kiosk and you’ll see a new mini-game called Bag a Bug. The first time you play is free but you have to pay 5 coins for the 2nd time and on. In this mini-game, your task is to collect as many bugs as you can within a time limit of 60 seconds. If Klubba attacks you, you’ll lose all the bugs you collected. If you’re attacked without any bugs in possession, the game prematurely ends. Be sure to hit any ! Barrels nearby to become invincible for a short while and Klubba won’t startle you. The more bugs you collect, the more prizes you’ll earn.
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https://www.youtube.com/watch?v=LKoBeq7Ct8U
This requires a Member Card that can be obtained via Nintendo Event. Speak to a green man at any Pokémon Center to get the Member Card. With this item, go to Canalave City and enter a house that was previously locked but now open. You may want to save your game before entering the house. A sailor will tell you that you’re about to have a nightmare and you’ll end up on Newmoon Island. Enter the forest where Darkrai is. Darkrai is on Level 40. It has an ability called Bad Dreams, which slightly damages sleeping opponents every turn. Darkrai has a combo using Hypnosis and Nightmare. Wait until night time and use Dusk Balls. After the battle, you’ll find yourself back at Canalave City. When Darkrai reaches Level 66, it will learn its signature move called Dark Void. Dark Void puts all opponents to sleep.
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https://www.youtube.com/watch?v=izdzFLVWBkY
At the Lostlorn Forest, where you found a TM95 (Snarl), there is a Hidden Grotto. Enter this Hidden Grotto and you might encounter a special Leavanny. It ranges between Levels 20-25. It also has the hidden ability, Overcoat. Overcoat makes the user immune to damage from weather effects, such as from sandstorms and hail.
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https://www.youtube.com/watch?v=Rv8hsbvJxyE
First, bounce off a spring by a Blargg in the lava. After some Buzzy Beetles, you’ll see Chargin’ Chucks throwing footballs. You can go up the pipe to cross platforms by an Amazing Flyin’ Hammer Bro or continue ahead and touch the checkpoint. Go through the pipe and go downhill with Buzzy Beetles. Go all the way downhill and go through the next pipe. You’ll see Spike Tops and yellow floors sinking into the lava. After a swarm of Chargin’ Chucks, cross more yellow floors sinking and you’ll find the only Yoshi Coin of the course. Go through the pipe and you’ll find the goal.
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https://www.youtube.com/watch?v=oThSh3XJbGc
Hit the button and the door will open. Once inside, fall down one floor and teal crows will fly by. Descend a few floors until you find a switch to hit and descend to the next floor. After going downstairs again, a caveman will throw spears. Make your way upstairs and you’ll encounter a caveman with a wasp flying around. This building serves as a maze with certain paths to take. Once you come to the point where you’re by a closed door, let the hawk press the switch to open the door and go through it. You’ll next battle against Amin. Amin will throw axes, so dodging can be pretty difficult. After defeating Amin, you’ll receive one of the 8 jewels and have a feast with Amin.
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https://www.youtube.com/watch?v=93jMNiQz_IM
Under a big rabbit, copy off an ember for the Fire ability and do a flame charge to break hard blocks. Break star blocks with Waddle Dees and go through the door ahead. Ascend the next area using the ladders while you’ll see big metal stones, bats, and Gordos. Go through the next door and use the Fire ability to burn a bush holding a flame panel that burns the branches so you can grab the first chest. Enter the next door and you’ll see a big chest on the platform. Spinni will appear to get there first so grab the chest on the platform and go to the goal ahead. The next 2 treasures are the Yellow Spray Paint and a Star Seal.
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https://www.youtube.com/watch?v=K4AU8TY-Y34
After triggering a flashback that showed N in the Chargestone Cave via Memory Link feature, his Pokémon will be released and scattered all over Unova. Explore the Chargestone Cave and you just might encounter a Ferroseed that will sparkle, representing that N used to own it. It will be on Level 28. It has a Bashful nature and the ability Iron Barbs, damaging those that make direct contact. Once you capture this Ferroseed that N formerly owned, you cannot give it any nicknames.
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https://www.youtube.com/watch?v=eBfjRf3DWds
Descend for the first time and you’ll see hatches releasing plasma strips. Descend again and you’ll see a sumo blower use its fan to push you back. As you keep descending, laser beams will try to block your path, so even if you touch one of them, you’ll easily be defeated. After collecting an Energy Tank, more hatches releasing plasma strips are in the next path. In addition, sumo blowers will try to force you back. Continue to descend and more laser beams will come in. You may want to use the Time Stopper to stop the lasers from going anywhere. Continue to descend and you’ll see spring traps. Use the cap doors and you’ll take on Quick Man. Quick Man will jump around and throw boomerangs. Defeat Quick Man and you’ll receive the Quick Boomerang weapon.
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https://www.youtube.com/watch?v=XeujnsdjI5M
Opelucid City’s gym features a puzzle with dragon heads adjusting and to choose a path to battle trainers. After different types of battles, keep using the dragon statues to move up and you’ll battle the gym leader. Drayden uses Dragon type Pokémon. Druddigon has the ability Sheer Force that causes more damage although the moves have their added effects eliminated. Flygon will use Earth Power to lower the target’s Special Defense stat and Rock Slide to make the target flinch. Haxorus will use Dragon Dance to gain power and Slash for critical hits. After the battle, you’ll receive the Legend Badge and a TM82 (Dragon Tail). The user moves last when using this move and when it strikes, it forces the opponent to switch out for another Pokémon. If Dragon Tail hits a wild Pokémon, the battle ends.
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https://www.youtube.com/watch?v=tPAofeamXRU