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Dry reforming of methane (DRM) is gaining global attention due to its capacity to convert two greenhouse gases together. It proceeds through CH₄ decomposition over active sites (into CH_4−x) followed by CH_4−x oxidation by CO₂ (into syngas). Furthermore, CH_4−x oligomerization into coke cannot be neglected. Herein, xNi(5−x)Co/Pd+Al₂O₃ (x = 5, 3.75, 2.5, 1.25, 0) catalysts are prepared, investigated for DRM, and characterized with X-ray diffraction, UV-Vis, transmission electron microscopy, temperature-programmed reduction/desorption techniques, and thermogravimetry. Fine-tuning among stable active sites, graphitic carbon deposits, and catalytic activity is noticed. The total reducibility and basicity are found to decrease upon increasing the Co proportion up to 2.5 wt% in the Ni-Co bimetallic Pd+Al₂O₃-supported catalyst. The active sites derived from strong metal–support interaction species (NiAl₂O_x or dispersed CoO_x) are found to be promising in higher levels of activity. However, activity is, again, limited by graphitic carbon which is increased with an increasing Co proportion in the Ni-Co bimetallic Pd+Al₂O₃-supported catalyst. The incorporation of 1.25 wt% Co along with 3.75 wt% Ni over Pd+Al₂O₃ results in the generation of fewer such active sites, extensive oxidizable carbon deposits, and inferior catalytic activity compared to 5Ni/Pd+Al₂O₃. The 2.5Ni2.5Co/Pd+Al₂O₃ catalyst has lower crystallinity, a relatively lower coke deposit (than the 3.75Ni1.25Co/Pd+Al₂O₃ catalyst), and a higher number of stable active sites. It attains a 54–51% H₂ yield in 430 min TOS and 0.87 H₂/CO (similar to 5Ni/Pd+Al₂O₃)