Phil Coulson

Phil Coulson was brutally killed by Loki in the first Avengers movie and his death was used as a motivational tool to get the titular team to band together in the final fight against the Asgardian villain’s alien army.

Of course, since then, Coulson has been revived using alien DNA and is now the star of the brilliant Marvel Cinematic Universe television show Agents of S.H.I.E.L.D. – but, as far as the Avengers are aware, he’s still dead.

Given that he was their friend, it seems unfair that they don’t know he’s actually alive and it would have been great to see him appear in Avengers: Age of Ultron – perhaps when Nick Fury arrived in a S.H.I.E.L.D. Helicarrier to assist in the final battle (especially since he was said to have orchestrated the whole thing). Audiences would have loved it, given Coulson’s popularity with fans, and the reactions of the likes of Tony Stark and Steve Rogers would have been wonderful to see.