From Marvel it is always stated that they have a well thought out plan regarding their cinematographic universe, but the truth is that one can find several continuity errors over the years. That yes, none goes back as far back in time as the plot line opened by ‘The Incredible Hulk’ from which later it was never known.
The Marvel Leader
I am referring to the fact that in the film starring louis leterrier we can see how the character played by Tim Blake Nelson he comes into contact with Bruce Banner’s blood and his head begins to transform. Then ‘The Incredible Hulk’ focuses on the epic battle against Abomination, completely forgetting that other point.
The truth is that Nelson was going to become Leader, a very recurring villain in the Hulk comics. The actor himself acknowledged at the time that he had signed a contract to appear in two more films -the first one was even said to be similar to Christopher Nolan’s Batman- and years later, when it was already known that Mark Ruffalo was going to replace Edward Norton like Banner, he stated that he was still interested in reprising the character.
In the comics, Leader was the alter ego of Samuel Sternswho was also exposed to gamma radiation, which transformed him into a green creature with high intelligence that repeatedly faced the Hulk.
The only official explanation that they have given in Marvel to set aside this plot came in 2017 from the hand of Kevin Feigwho commented the following in this regard:
If you can’t do it right, don’t do it or do it later, and the thought of ‘Hey, I’m here too! Following!’ we are not interested.
Come on, it doesn’t fit them well, so they left it aside, something that was surely influenced by the fact that ‘The Incredible Hulk’ did not achieve the success expected by the studio. We’ll see if that changes in the future, because Marvel recently recovered Tim Roth to bring Emil “Abomination” Blonsky back to life, so they could always do the same with Nelson. However, I am not optimistic about it and most likely it will simply accumulate more years being Marvel’s first big continuity mistake.