The following simulations are of EAS interacting with the Milagro Gamma Ray Observatory. Milagro is a water Cherenkov detector where the particle front of the EAS converts into a front of Cherenkov photons. Studying the movies one can observe many expected effects such as refraction of the showerfront, as well as several novel behaviors like bifurcation. For a full explanation of the physics involved please see the Explanation below.