The current discussion around 'The Avengers 2' has shifted from the stars demanding higher pay to something equally inside baseball: the rights to the characters of Quicksilver and the Scarlet Witch. In the pages of the comics, they're mutants and Avengers, which has led to a pretty sticky situation. Fox, who has the X-Men rights, plans to use Quicksilver for the upcoming 'X-Men: Days of Future Past.' Marvel and writer/director Joss Whedon plan to use him for 'Avengers 2.' This conflict remained hidden when Whedon went on Late Night to chat about the characters with Jimmy Fallon.