The team behind Square Enix's Einhander helped develop the expansive Gummi Ship aspect of Kingdom Hearts III. They even included references to Einhander, including an unlockable Gummi Blueprint obtained by scanning a constellation in the Misty Stream area that greatly resembles Einhander' Endymion ship. One of Einhander's bosses, the Schwarzgeist, also cameos as a boss in Kingdom Hearts III, and a remix of Einhander 'Thermosphere' plays when the boss is fought with most Gummi ships. However, if the boss is fought with the Endymion blueprint, then the original PlayStation 1 version of the Thermosphere theme will play.