We know that the Marvel Cinematic universe will include 67 characters who are likely to appear in Avengers Infinity War Part 1 and 2. The studio executives attached to the project further clarified that there will be new titles for the final two movies as they are two independent movies without any major inter-linkages. In the first part, Thanos will collect all the mind gems and may even assemble an Infinity gauntlet, cause a world-wide catastrophic event and then in the next part Avengers will unite against an invincible adversary and fight him to save the world. But in the process, they will do irreparable damage to the mankind.
Kevin Fiege (President, Marvel Studios) has teased the phase 4 of Marvels cinematic universe, and is touting it as something never seen before in Marvel films. He said “I think you look at the comics as a guide, although some titles get rebooted or re-launched, the narrative exist on a never-ending continuum”. What is really mean by this is if the studio decides to cast someone else in place of an established character, everything that has happened will continue to exist. For instance, if Marvel brings Kate Bishop into the cinematic universe as a new Hawkeye in place of Clint Barton (as he may have family issues) or Sam Wilson (The Falcon) taking the mantle of Captain America as Winter soldier decided to go under at the end of Civil war, it would’nt erase the Steve Roger’s past. The most beloved character of Iron Man will continue to be the most pivotal guy who links Avengers stories across space and time. He further said that Marvels phase 4 will mark a new beginning and a very distinct chapter comprising of finality of all the previous phases. It would probably include The Inhumans, Black Panther sequel, Captain Marvel sequel, Dr. Strange sequel, Guardians of the galaxy 3 etc. One thing which is absolutely clear looking at the roster of superhero movies in the pipeline is that we will see a huge influx of mysticism and magic in Marvel movies in phase 4.