Here, we use a predictive design strategy to realize the on-surface synthesis of two homologs of Clar’s goblet, via lateral and vertical extensions of the parent structure, respectively. Vertical extension increases the number of topologically frustrated zero-energy modes, which scales linearly with the total number of benzene-ring rows. By contrast, lateral extension enhances electron–electron interactions, leading to the emergence of additional radical states beyond those predicted by the topological zero-energy modes. Consequently, both structures exhibit correlated tetraradical character and a many-body singlet ground state, as confirmed by multireference theoretical calculations. These magnetic states arise from distinct magnetic origins and exhibit distinct resilience to external perturbations, as experimentally validated using nickelocene-functionalized scanning probe techniques. For more details. see.