I am wondering what approach to take for generating dynamic slime blob similar to Natural Selection 2's Dynamic Infestation.

Here is a video:

Two Things:

1) I am working on Unity.

2) I have experience manually creating meshes like spheres and other shapes, but am unsure what shape to use and how to knit together multiple mesh peices.

Any ideas for an approach I may test out would be appreciated! Thanks.

I could be leading you astray but could you have a multitextured surface where the geometry covered by the "infected" texture is subdivided in the geometry shader than displayed in the vertex shader?