It appears that at some point during development Metal Gear Solid 5 had a Mission 51, according to a video taken from the game’s collector’s edition bonus content Blu-ray.
The article contains spoilers which you might not want to see if you’re yet to finish Metal Gear Solid 5: The Phantom Pain.
The video shows what appears to be an alternate or supplemental final game sequence, offering some insight into key character development for later games (chronologically) in the series. It’s certainly worth a watch but remember it does feature spoilers.
It’s not clear why the sequence isn’t found in the shipped game, but we can hope Konami has plans to release it as DLC of some kind.
Let us know what you think of the new ending in the comments below.