Metal Gear Solid: Integral

Metal Gear Solid: Special Missions was an "expansion pack" for Metal Gear Solid, "expansion pack" because it needed an original copy of MGS in order for you to play it, asking you to insert either disc one or two (didn't matter which one) upon loading the game.

The game contained loads of extra VR Missions to complete, including severeal wierd missions (such as taking on a gigantic GENOME Soldier) and also contained a few hidden surprises, including the option to play as Cyborg Ninja.