Relic Castle (Japanese: 古代の城 Ancient Castle) is a large castle in the middle of the Desert Resort. It is comprised of five different floors in the form of a maze. In Pokémon Black 2 and White 2, a very strong Volcarona (which can be caught), appears in the central room of five rooms accessible from the Relic Passage. In Pokemon Black and White, toward the lowest floor of the castle, Ghetsis is found, as well as Cheren and the Champion who are investigating the castle along with you for the dark/light stone. It is riddled with patches of quicksand which will pull you to a lower floor if you stand in the middle or try to run through it. Often though, these quicksand patches are necessary for the exploration of new areas of the castle.
During the main game, you can only access the top floor of the Castle itself and the 1st floor of the underground Part of the castle.
After the main game has been completed, you can go to the Relic Chamber and find a mountain of sand. Through the hole at the top, there is a couple of rooms and a Team Plasma Grunt. Defeat him in battle, get to the Volcarona Chamber, and you will find Ryoku. He will give you a TM and grant you access to the Main Chamber. There, Volcarona is waiting.
Exit the castle, go back to the Relic chamber, and then enter the maze again. Keep going left, and you will eventually reach a room with stairs. Keep going up the stairs and you eventually reach the Relic Castle-Castle. You will be on the raised floor. There, you can find the TM Earthquake.
A Backpacker will offer you a fossil which you could revive at Nacrene City. Note that you can only get one fossil, so choose wisely.
Abundant Shrine · Abyssal Ruins · Battle Subway · Castelia Park B2W2 · Castelia Sewers B2W2 · Casteliacone · Cold Storage
Desert Resort · Dreamyard · Entralink · Entree Forest · Floccesy Ranch B2W2 · Hidden Grotto B2W2 · Join Avenue B2W2 · Liberty Garden
Marine Tube B2W2 · Moor of Icirrus · Plasma Frigate B2W2 · Pokéstar Studios B2W2 · Relic Passage B2W2 · Royal Unova
Undella Bay B2W2 · Underground Ruins B2W2 · Virbank Complex B2W2 · White Treehollow B2W2
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