Here's one of the few things Call of Duty 4 players need to know about the remastered version; other than its new features including enhanced textures, rendering, high-dynamic range lighting, the remastered version also have new trophies to earn but still covered most of the trophies from the original game.
In the Modern Warfare Remastered's website, there was an update that talked about having the need to insert the Call of Duty Infinite Warfare disc to be able to play the game. In the previous update, it was announced that Modern Warfare Remastered was made to be a digital-only game; which can only be accessed through Infinite Warfare's premium editions (Premium Editions starts at $80).
In the update, it said "Modern Warfare Remastered is a full game download (game disc must be inserted to play Modern Warfare Remastered). Internet connection required." The update had lead to a lot of confusions and questions from fans that had the Activision put up a site to answer all frequently asked questions, although there are still no further details about the part where the disc must be inserted to be able to play the game.
Charlie Intel reported that this wouldn't apply to those who are going to buy the Infinite Warfare digitally because it does not come with a disc.
Players who have purchased the premium version of Call of Duty: Infinite Warfare in advanced on PlayStation4 will be able to play Call of Duty 4: Modern Warfare Remastered campaign on the 5th of October, Wednesday. The game progress will carry on, so there's no need for the players to worry about starting all over again when Infinite Warfare comes out on the 4th of November.
Multiplayer support will also be included in the Modern Warfare but will still not yet be available until the launching of the game.