I have a decent NES game collection. I started collecting nearly 20 years ago. I assumed I had nothing that was considered especially rare or valuable because what was considered rare and valuable back then was stuff like Tengen Tetris and the Panesian games. I probably got Power Blade 2 for like 5 bucks at a Funcoland.
It’s crazy what has gone up in value and what hasn’t. Tengen Tetris was my holy grail for a long time. I found a copy for 30 bucks and slapped down the money, no question. Still my favorite version of Tetris by far. Whenever I first started collecting (also about 20 years ago) it was one of the higher end titles. I haven’t looked to see what it’s worth lately but it’s one I do regret selling.