Metal Gear Solid: Ground Zeroes has an interesting piece of PlayStation 4 exclusive content - a mission in which you play as Solid Snake, from MGS, MGS 2 and MGS 4, as opposed to Big Boss, the Snake seen in Ground Zeroes and The Phantom Pain.
Similar to the flashback mission seen in Metal Gear Solid 4: Guns of the Patriots, the missions is rendered in the original, low-poly count models of the first Metal Gear Solid on the PSOne.
The mission was announced during the Spike TV PS4 All Access last night. Kojima said it's special mission exploring the "Shadow Moses-ish GZ base," and that "on Monday next week, "Déjà-Vu Mission"'s further detailed trailer will be posted on our official site. This one can be easier to understand and even funnier."
Metal Gear Solid: Ground Zeroes is coming to PS3, PS4, Xbox 360 and Xbox One in northern spring 2014. It is a prequel to Metal Gear Solid 5: The Phantom Pain.