Marvel fans are talking about the biggest mistakes the MCU has made - and everyone seems to agree on one particularly tragic moment

Marvel fans are debating the biggest mistakes the MCU has made - and we do have to agree with some of them.

The discussion, which took and is still taking place in none other than r/MarvelStudios, has over a thousand comments from passionate fans - and we've selected the most popular few.

"For me, it was killing Pietro. I absolutely love their duo with Wanda and chemistry between the actors," one fan wrote in what seems to be the most popular and agreed-upon response. "He was [a] fun and interesting character that could be very useful in the next big movies. How many great action scenes and team-ups we were robbed. Ouch."

Aaron Taylor-Johnson recently spoke about his slain character, who died in Avengers: Age of Ultron, jokingly asking the question: If Pietro was Wanda's brother, why didn't she just use her powers to bring him back?

"Hiring the king of mo-cap actors Andy Serkis to play a character who in the comics is transformed into a bright pink being made of solidified sound and one of the most iconic Black Panther villains of all time and then having him be shot to death as a human without even interacting with T'Challa," wrote another. Serkis played Ulysses Klaue, who is very much a supervillain in the comics. In Black Panther, however, his villain transformation - in which becomes solid sound and thus very difficult to defeat - doesn't happen.

A comment with over 2,000 upvotes plainly stated: "All of Secret Invasion," with another echoing, "G'iah." Secret Invasion was quite the show - and it ended with a major MCU event that still hasn't materialized in any other Marvel film or show. The series began with the controversial killing of beloved character Maria Hill, and ended with G'iah (Emilia Clarke) possessing the power of every single Marvel superhero. This essentially makes her more powerful than Thanos - and we haven't seen her since.

"How Gorr was handled. Don't pick a villain with insanely heavy subject matter if your goal is to make a romp," someone else said. "Should have been Mangog." Gorr, played by Christian Bale, appears in the superhero romcom Thor: Love and Thunder. He does feel a bit misplaced, however, given his tragic and violent backstory and mission to, as his name implies, kill every single god he comes across.

For more, check out our list of all the upcoming Marvel movies and shows you need to know about.