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The 2019-2020 Australian wildfire crisis broke the historical bushfire record and heavily contaminated the continental and offshore atmosphere. This study found that lightning strokes increase considerably, by 73% over land and 270% over ocean, during the wildfire season. Thermodynamic parameters support a weaker forcing, unfavorable for frequent lightning activity over ocean. Clear augmentation of smaller cloud ice particles is identified with aerosol, while cloud liquid water path changes are feeble over ocean. Added aerosol invigorates positive intra-cloud (IC) strokes and negative cloud-to-ground (CG) strokes in moist oceanic convection and facilitates a noticeable positive correlation between precipitation and lightning strokes. Rainfall events accompanied by lightning increase by 240% with added aerosol. Aerosol advected from land to ocean can lead to a larger hydrometeor concentration and smaller-size ice crystals above the freezing level and thereby, invigorate convective strength systematically to stimulate more frequent and more robust mixed-phase development, energizing the lightning discharge process. Plain Language Summary The notorious 2019-2020 Australian wildfire devastated >46 million acres of land and heavily contaminated the atmosphere over the Australian continent and offshore regions. In conditions of moist convection over the polluted ocean, massive heat from wildfires on land is ineffectual and aerosol effects can be disentangled from the thermodynamic factors in lightning response. This study focuses on this natural experiment and addresses the lightning changes during the wildfire season by checking both thermodynamic parameters and cloud microphysics. Results of the average surface temperature, convective available potential energy, Bowen ratio, and latent and sensible heat flux support a weaker thermodynamic condition for relatively infrequent lightning activity, crediting aerosol effects for the observed lightning enhancement of 270% over the polluted ocean. Added aerosol mainly invigorates the positive intra-cloud (IC) strokes and negative cloud-to-ground (CG) strokes in oceanic convection. A noticeable positive correlation between precipitation and lightning is identified. Rainfall events accompanied by lightning activity increase by 240% with added aerosol. Clear evidence is shown for an augmentation of smaller cloud ice particles, while changes of the cloud liquid water path are feeble over the polluted ocean. Added aerosol energizes the convective strength systematically and more frequent and robust mixed-phase development invigorates lightning discharges. [ABSTRACT FROM AUTHOR]