Who are the Aliens in Marvel's The Avengers ?

The fans on the SuperHeroHype Forums made these animated gifs using the new "Head Count" TV spot for Marvel's The Avengers to give us a good and repeated look at "Loki's Army" in the anticipated May 4 release.

Who do you think these aliens are? Have we seen them before in the comics? Are they something new created for the movie? Are they Michael Bay's Ninja Turtles ? Let us know what you think in the comments!

Source: http://www.comingsoon.net/news/movienews.php?id=88633

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