Black Key

Black Keys are items in Paper Mario: The Thousand-Year Door that open the four black chests. Each chest contains the soul of one of the four heroes that originally sealed away the Shadow Queen. Upon opening the chest, they "curse" Mario and give him a new Paper ability on the field.

The first Black Key is found in the Rogueport Sewers. Mario must press the nearby ! Switch to uncover a staircase to reach it. The second key is found in a chest in Hooktail Castle. Once it has been collected, spikes rises from the ground while the ceiling slowly falls. The third key is found in a shack just outside of Twilight Town. The fourth key is obtained at Pirate's Grotto by defeating the Ember that appears after speaking to the black chest.

Names in other languages
Schwarzer Schlüssel Chiave nera