Err: The 1990 Incident

The night before the Tokyo Toy Show in 1990, an unknown person broke into Sega's HQ, the cartridge that was meant to be shown got replaced by a different one. This resulted an incident happening and the company threw it out in the garbage. One day, while scrolling through eBay, you managed to find the cartridge from the Tokyo Toy Show, since it was a once in a lifetime opportunity, you bought it because you were curious to find what's in it.