Marvel Studios and Disney are currently in the middle of Phase 3 of the Marvel Cinematic Universe, with "Doctor Strange" and "Guardians of the Galaxy Vol. 2" releasing in the months to follow. Phase 4 currently only has one film confirmed, "Guardians of the Galaxy Vol. 3," and director James Gunn isn't sure he'll even return to helm it.

Responding to several comments on his official Facebook page, Gunn explained that the process of directing these films was exhausting and emotionally taxing despite the fact that he was attached to the characters and was having fun directing them.

"I'm not yet sure whether I'm going to do 'Vol 3.' This one ['Vol. 2'] was more emotionally exhausting," Gunn explained to the fans commenting on his recent post. "I love these characters and the performers and visual effects artists who help me bring them to life and I'm grateful to have spent the last few years working with them."

Fans will recall that this mirrors the same sentiments shared by Joss Whedon after he directed both "Avengers" and "Avengers: Age of Ultron." At the time, Whedon expressed exhaustion and the need to work on something smaller. Due to this, Whedon is not directing "Avengers: Infinity War" parts one and two as the duties have been passed to the Russo brothers, who directed "Captain America: Civil War."

Back in April, Marvel Studios executive Kevin Feige confirmed that "Guardians of the Galaxy Vol. 3" is going to happen and it is the only confirmed film thus far for MCU Phase 4. Feige explained that at the moment the studios are solely focused on the films they will release until 2019 and 2020. 

Despite this, it is heavily implied that there will be a sequel to "Doctor Strange," "Ant-Man and Wasp," "Captain Marvel" and "Black Panther." A solo "Black Widow" movie has also been rumored for some time.