Since the European cartridge is encoded for PAL regions, the game would not work properly on a North American NTSC NES due to graphical glitches, but an identical NTSC prototype ROM has been leaked online which functions properly.
Since the European cartridge is designed for PAL regions, it wouldn't function correctly on a North American NTSC NES because of graphical issues. However, an identical NTSC prototype ROM has been leaked online that operates flawlessly.