Complex sentence: The mother D-Reaper appeared in the real world in the form of a large red goo, it rapidly expanded as it devoured and deconstructed material to build itself, a sort of amoeba like life form.
Split into simpler sentences: The Mother D-Reaper appeared in the real world in the form of a large red goo. It rapidly expanded as it devoured and deconstructed material to build itself, a sort of amoeba like life form.