The near mythical cart was only manufactured an alleged 116 times as it was created exclusively for the US-based Nintendo Entertainment System tournament in 1990. 90 copies in a grey cart - like the one currently on sale - were distributed to the competition's finalists, while another 26 were forged with special golden cartridges and given away as part of a Nintendo Power contest.
At the time of writing the current bid is up to $91,200 with 10 hours remaining.