In addition to discussing Quicksilver and Scarlet Witch (sounds like maybe they'll be fighting The Avengers at least initially), Joss describes the feeling of directing characters he grew up reading and the responsibility he shoulders to reinterpret these characters for children just coming of age and discovering these superheroes for the first time.
"We are introducing Quicksilver and Scarlet Witch who are mainstays of The Avengers universe, they're foes, they've been allies and they're very interesting to me because I grew up reading The Avengers. They have powers that are visually exciting, different from the characters we've seen before so I'm excited to knock them against The Avengers and see what shakes loose."
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