Black Tower

Black Tower (Japanese: 黒の摩天楼 Black Skyscraper) is a battle area initially exclusive to Pokémon Black 2. Located in Black City, it is the counterpart to the White Treehollow of Pokémon White 2. It can be accessed after Black Tower is unlocked with the Unova Link's Key System. If a player of Black 2 clears Area 5 of the Black Tower, that player can send the Tower Key to White 2 players, granting them access to Black City.