After MINIMCOM's airframe was replaced by constructors, specially modified versions of the VIRUS units, his entire shape became mutable. When Rei and Rome had to fly to Earth, MINIMCOM expanded large enough to envelope the entire flying house.
Another use of these constructor units was to build livetars (amalgam of live avatars) which were basically ambulatory shells. They are typically hollow. They have no consciousness. They are just extensions of MINIMCOM's airframe: a walking set of hands and a speaker.
Later in the story, MINIMCOM fills the heads of some livetars with memrons so that they were semi-autonomous and he filled their hands with active VIRUS units to help dissolve the asteroid that threatened Deucado.
OMCOM learned of the technique from MINIMCOM, initially borrowing MINIMCOM's constructor units but later fabricating his own.
MINIMCOM's livetar is all black and he wears a cape for dramatic effect. OMCOM's livetar is all white. Later, in the novel The Ark Lords, you will meet another all-gray livetar called Junior.