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Metal cyanide clusterfullerenes (CYCFs) are formed via the encapsulation of a single metal atom and a cyanide unit inside fullerene cages, endowing them with excellent properties in various applications. In this work, we report the synthesis, isolation, and characterizations of the first cases of thulium (Tm)-based CYCFs with the popular C₈₂ carbon cages. The structural elucidation of the two TmCN@C₈₂ isomers was achieved via diverse analytical techniques, including mass spectrometry, Vis-NIR spectroscopy, single-crystal X-ray crystallography, and cyclic voltammetry. The crystallographic analyses unambiguously confirmed the molecular structures of the two TmCN@C₈₂ isomers as TmCN@C_s(6)-C₈₂ and TmCN@C_2v(9)-C₈₂. Both TmCN clusters adopt a well-established triangular configuration, with the Tm ion located on the symmetrical plane of the carbon cages. The electronic structures of both TmCN@C₈₂ isomers adopt a Tm³⁺(CN)⁻@(C₈₂)²⁻ configuration, exhibiting characteristic spectral and electrochemical properties reminiscent of divalent endohedral metallofullerenes (EMFs). Intriguingly, unlike the divalent Tm²⁺ ion observed in the mono-metallofullerenes Tm@C_2n, a higher oxidation state of Tm³⁺ is identified in the monometallic TmCN cluster due to bonding with the cyanide anion. This result provides valuable insight into the essential role of the non-metallic endo-units in governing the oxidation state of the metal ion and the electronic behaviors of EMFs.