Missed this thread. I have a large collection and from quite early on I had an eye on the individual games from NES to PS2 that were obviously going up in price. So I have quite a few of the individual games that have already been named in this thread. My default answer to this has always been Castlevania SotN on PS1, which for so long was just the most expensive game that I was generally aware of. I’ve just checked recent solds and it’s up to around £600 now.
The only game that immediately comes to mind that might be worth more is Castlevania 3 on the NES. But that’s actually very rare now and I can’t even find any sold listings on Ebay.
However, I do have a sealed copy of Final Fantasy Adventure on the Gameboy. I don’t collect sealed games generally, but I bought that myself from EB in about 2002 and just never opened it. I have no idea what it’s worth but a collector would probably pay close to four figures for it I suspect.
Not that you guys wouldn’t believe me, but proof;
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