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The Secret Bazaar is a location that can be entered by randomly finding a hidden staircase inside dungeons in Pokémon Mystery Dungeon: Explorers of Sky. It is run by a Kirlia and has four stands that each provide a beneficial service to Exploration Teams for 100 Poké. After exiting the Secret Bazaar, the Exploration Team will be on the floor directly after the floor that they were on before entering Bazaar.
The day before the Wigglytuff Guild goes on its expedition to find Fogbound Lake, Diglett is at the crossroads and asks to be told if the Secret Bazaar is found during the expedition.