According to producer Kevin Feige, the Bifrost bridge is the films's most interesting set: "In the comics, it's literally a rainbow that extends out from Asgard and pops down on Earth. We're not necessarily doing that; we're not having the big hard solid lines of colors. We're saying it's some sort of energy, almost a solid quartz bridge that as the light catches it and flows through it, you get some of that rainbow-esque quality to it."
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