Valkyries
Latest reports suggest that Mark Ruffalo’s Bruce Banner a.k.a. Hulk would be returning in Phase 3 before the next Avengers movie, and that it could be in Thor 3. Confirming that news with their own source, BMD reports that this is indeed the case. They also add that the "Thor: Ragnarok" screenplay by Christopher Yost and Craig Kyle is too dark, hence why Taika Waititi was brought in to direct and tweak the picture. Another writer may join the creative team too to lighten it up to fit the Marvel formula.

According to Screenrant.com, the latest development could be good or bad news depending on who you ask, but the exciting stuff comes in the newly revealed Thor 3 story details.

BMD’s inside sources reveal that Hulk’s role isn’t just a guest appearance, but a lead part where he and Thor will enjoy a “cosmic adventure” of sorts. They’ll come across the Valkyries on their journey and yes, there’s a very real possibility the Valkyrie readers may recognize from the Defenders, Secret Avengers, Ultimates, Marvel video games and the Hulk vs. Thor animated feature, known as Brunnhilde will be introduced.

The Valkyries, in the Marvel Comics and Norse Mythology, are the goddesses who choose the worthy fallen warriors from the battlefield to bring them to Valhalla. There they feast and prepare for Ragnarok (the end of the universe). And from what Marvel Studios boss Kevin Feige said last year when announcing the title "Thor: Ragnarok," the movie will have a major impact on the Marvel Cinematic Universe as its name implies.

So, not only is Hulk leaving Earth in Phase 3 to join Thor in this event, but Marvel may introduce another powerful Asgardian superhero who could make her way to Earth eventually. Interestingly enough, Valkyrie almost debuted in "Thor: The Dark World." Marvel Studios commissioned concept art during pre-production but decided not to use the character.

BMD doesn’t have the precise details on the Valkyries and how they’ll factor into the "Thor: Ragnarok" story yet, but if Brunnhilde is introduced, Marvel Studios may have solved their long-term Thor problem. Chris Hemsworth’s contract, like many of the other original Avengers stars, ends with "Avengers: Infinity War" and if Marvel Studios boss Kevin Feige – who does have more financial freedom now as the real boss of the film division – can’t re-sign the Aussie star, there’s a logical way to continue the series.