The first ever Daicon to use an opening animation was Daicon 3, where a parody of the science patrol gives the Daicon girl a glass of water, only to have Gundams, Godzilla, the Baltan Aliens, Mazer Tanks, Atragon, Ghidorah and even Gamera hunt her down.Perhaps the more famous Daicon intro animation was the one for Daicon 4, where the Daicon mascot girl is now an adult and fights off Gundams, Darth Vader, Super Sentai mechs, Kaiju, and others. All to the music of the Electric Light Orchestra. And that video is known for having the biggest cross over in animation history. So enjoy this peice of history, because we'll never have such great animation and so many anime/scifi stars together in one place again.
The cameos are almost endless, it even has Lupin the Third and Lum Invader, the Justice League and more.