This is my theory on how Makuta Shape-Shifts:
Makuta went from a Tohunga, To a Vortex of Infected Peices controled by an Infected Mask
Later he went from a Vortex of infected pieces controled by a Kraahkan (see recent update), to Makuta 2003.
I have concluded, by these facts, that Makuta can only shapeshift into a swirling mass of pieces fontroled by a mask, and then, if he wants a diffrent form, the pieces all combine into it, and the new form has the mask he has chosen. That is why Makuta 2003 has that look where he is kinda scrapped together with loads of diffrent pieces. What do you think? Post your opinion here.