Kevin Feige's cinematic universe is known not only for simply adapting the characters from the comics.
The Marvel Cinematic Universe has brought to screens many iconic superheroes, from the classic characters like Iron Man and Captain America to new fan favorites such as Ms. Marvel and She-Hulk.
Aside from that, the MCU has introduced plenty of its own original characters. For instance, in 'Moon Knight', the Marvel universe welcomes Layla Al-Fouli as a new avatar for the goddess Taweret in 'Moon Knight' and Sylvia as a female variant of Loki in, well, 'Loki'.
But there is one undisputed fan favorite in this list, and it is Phil Coulson – whose first name, as known by OG Marvel fans, is "Agent".
Due to fan love that Coulson enjoys, his character had quite a storyline in the MCU before being killed off in the first 'Avengers' movie.
"Wasn't Clark Greg cast because Agent Coulson was supposed to be a one-off minor character Favro just cast the first guy that looked suitable he saw, his neighbor? Then the audience liked him so much that they made him a recurring character and even made him part of the main cast in Agents of Shield. The stars just align sometimes." – /darewin
Even those who really grew to love Sylvie in 'Loki' admit that Coulson is definitely the best original MCU character.
"I really like Sylvie, and can't wait to see more of her, but it has to be Coulson. Not only is he an integral part of the MCU, but his development over the best part of the last 15 years has been great to see." – /UltraRomero7
Coulson, portrayed by Clark Gregg, made his first MCU appearance all the way back in 'Iron Man' that premiered in 2008. He then appeared in the Iron Man sequel, as well as in 'Thor', and then heroically sacrificed himself in 'Avengers'.
However, his death did not prevent him from landing his own show, 'Agents of S.H.I.E.L.D.'. You know the character is good enough when he gets a show despite dying, don't you?