Following the announcement, Twitter user Nitroid found that the Metal Gear Solid website had added buttons to its franchise timeline for the games included in Vol. 1, plus placeholder buttons for Metal Gear Solid 4: Guns of the Patriots, Metal Gear Solid 5: The Phantom Pain, and Metal Gear Solid: Peace Walker.
After this discovery, IGN reported to have heard from sources that the three games are set to be included in Metal Gear Solid: Master Collection Vol. 2.