Cadmium (Cd) contamination in paddy soils poses a dual challenge to food safety and climate resilience, undermining rice productivity while influencing greenhouse gas (GHG) emissions. Although vermicompost (VC) and biochar (BC) have been widely studied as soil amendments, the comparative efficacy of pristine VC versus vermicompost-derived biochar (VC-BC) in regulating Cd dynamics, soil health and GHG emissions remain unclear. Here, we studied the potential of VC and VC-BC on Cd translocation and bioaccumulation in rice, rice growth, soil C fractions, and methane (CH 4) and nitrous oxide (N 2O) emissions across rice growth stages. Results demonstrated that both VC and VC-BC enhanced microbial biomass carbon and dissolved organic carbon, but VC-BC exhibited superior Cd immobilization, reducing grain Cd concentrations by 79% compared to 45% with VC. Unlike VC, which increased Cd bioaccumulation factors, VC-BC reduced Cd uptake while enhancing chlorophyll content, antioxidant defenses, and overall plant vigor. The dramatic effect of VC-BC, characterized by hydroxyl (-OH), carboxylate (COO -), amide (N-H), and aromatic (C=C) functional groups, enhanced Cd immobilization, reduced grain contamination supported by the porous structure identified using SEM. GHG emissions displayed stage-specific dynamics: CH 4 emissions were significantly higher during the tillering stage while N 2O emissions increased during transplanting and harvesting stage. VC-BC moderated these fluxes relative to VC. Collectively, VC-BC emerges as a climate-smart, multifunctional amendment that immobilizes Cd, sustains soil biochemical health, and mitigates environmental trade-offs in rice systems.