Grr.. I am really confused about Shadow's past. Did he die in Sonic Adventure 2 Battle? Is he an android in Sonic Heroes and Shadow the Hedgehog? And is he the so called "ultimate life form" or is that the bio-lizard thing?
1. No, Eggman saved him via his robots.
2. No, though some things try to lead him to believe that he is.
3. It's Shadow. The Biolizard is obviously not the true ULF as it's called a prototype several times.

~ Crazy C Lea