Infinity Wars has been announced to include a roster of 67 Marvel characters and I thought it would be a good time to take a look at the possible characters. From here we'll begin the breakdown with various sections depending on what characters are unconfirmed and work from there with list comprised of their super characters.
Confirmed Roster Members
Iron Man; Captain America, Hulk, Thor, Hawkeye, Thanos, Loki, Magus.
These characters are all officially cast, the next list is highly likely though there are still movies left for them to perish before hand though no one ever really dies in this universe it seems.
Mostly Likely Roster Members
War Machine; Black Widow, Black Panther, Scarlett Witch, Antman, Wasp, Dr Strange, Captain Marvel, Guardians of the Galaxy (5 members including Rocket Raccoon, Groot, Drax the Destroyer, Gamora and Star lord), Falcon, Iron First, Jessica Jones, Daredevil, Luke Cage, Spiderman, Winter Soldier, Punisher, Electra
Possible Roster Members
Vision, Fantastic Four, Dr Doom, The InHumans (multiple members possible), Phil Coulson, Sharon Carter, Thor Crew (Sif, Odin, Fandral, Volstagg), Nick Fury, Maria Hill, Hank Pym, Pepper Potts