We successfully demonstrate the morphological manipulation of complex three-dimensional gold nanocrystals. The control upon the nanoparticle crystal structure was achieved by the discovery of a new crystal growth kinetics regime where the number and length of arms as well as the nanocrystal size can be altered to produce a multitude of architectures. The synergetic relationship between chemical reaction components and possible mechanistic pathways is discussed. TEM tomography was employed to characterize the three-dimensional structure of the complex morphologies.