The first image to take shape, which eventually played a major role in the Black Dragon Series of playing cards, was the Black Koi (featured as the Joker in this deck series). It was created by Marine Loup back in 2014 after she felt inspired by a legend about a group of Koi fish. The legend goes that through determination and perseverance, a single black koi was able to swim upstream to reach the top of a waterfall against all odds. It overcame demons that laughed at and mocked its efforts and who had also heightened the waterfall out of malice. According to legend, after reaching the top of the waterfall, the gods who had witnessed the koi’s efforts turned the black koi into a Golden Dragon, the image of power and strength. This deck draws its inspiration from this legend and from Marine Loup and her Turning Japanese illustrations, and represents the determination and perseverance demonstrated by the black koi, battling against all odds to succeed. The black Koi, then, is the Joker, indicating that the demons made fun of its efforts to swim upstream.

Full deck scan by macstrat @ https://cardscans.piwigo.com/index?/category/330-black_dragon