In recent years, pathway complexity has been studied in detail for a large variety of organic and π-conjugated molecules. However, such investigations on their metal-containing analogues have received only little attention to date, despite the well-known potential of metal complexes in various fields. In this Minireview, we have collected recent examples of d8 metal complexes (Pt(II), Pd(II) and Au(III) complexes) exhibiting controlled supramolecular polymerization through pathway complexity and seeded-growth approaches. Controlling the competing thermodynamic vs. kinetic pathways in these systems should help develop advanced metallosupramolecular functional materials with excellent photophysical, electronic, magnetic, catalytic, and biomedical applications.