Final Fantasy XIII (O-ring)

Some collector's editions arrive with fanfare. Others slip in quietly through a single retailer and become the stuff of hunting legends. The Final Fantasy XIII O-ring edition on Xbox 360 is exactly that kind of sleeper, a cardboard sleeve variant with alternative cover art sold exclusively through HMV stores.

Nobody seems entirely sure why it's called the "O-ring," and honestly, that mystery only adds to its charm. What we do know is that Final Fantasy XIII marked the franchise's divisive leap into linearity, splitting fans right down the middle. Love it or loathe it, you can't deny it became a talking point.

And this particular variant, with its alternate artwork and limited retail window, has become one of those quiet shelf pieces that separates the casual collector from someone who really knows their 360 library. The HMV exclusivity means supply was already thin at launch, and time has only tightened that grip. If you're building a complete Final Fantasy collection across consoles, this is the kind of variant that fills a gap most people don't even know exists.

That's the best kind of find.