The present work describes the synthesis of a new triazole based ligand 3-(3,5-dimethyl-1-pyrazol-1-yl)-1-methyl-1-1,2,4-triazole (LM) and demonstration of its coordination diversity giving rise to a family of seven new coordination complexes, namely: Ni(LM)·CHOS (5), Co(LM)·(CH)O (6), [Cd(LM)Cl] (7), [Cu(LM)NO]NO (8), Fe(LM) (9), Zn(LM) (10) and [Zn(LM)NO]NO (11), whose crystal structure was determined by single-crystal X-ray diffraction. Cytotoxic activity was evaluated against the MDA-MB-468 cancer cell line, which serves as a model for triple-negative breast cancer, and compared to the precursor molecule (L), as well as their coordination complexes (HO){NiL} (1), CoL·2HO (2), [CdLCl] (3) and CuL (4), for which the crystal structure was earlier determined. Notably, cadmium complexes 3 and 7 exhibit remarkable cytotoxicity and demonstrated a high selectivity index towards cancer cells when compared to peripheral blood mononuclear cells. Such activity highlights their potential function as anticancer agents.