<p>Rainfall-driven infiltration rapidly changes pore pressure, effective stress, and shear strength in slopes, hence controls the short-term instability of slopes and post-storm landslide risk. To assess this risk, we developed a hydrogeophysical workflow based on a multi-geophysical approach to capture the change of corresponding physical properties caused by transient infiltration at a hillslope scale. This workflow integrates high-resolution electrical resistivity tomography (ERT), transient electromagnetics (TEM), multichannel analysis of surface waves (MASW), and audio-frequency magnetotellurics (AMT) methods, and targeted boreholes are incorporated to assist interpretation. Time-synchronized surveys are conducted immediately after rainfall, and multiple geophysical data sets are inverted and jointly interpreted via a unified framework to study near-surface resistivity and shear-wave velocity signatures. The integrated view indicates a perched and laterally continuous saturation in the crest fill, an arcuate shallow weak plane, and deeper fracture-controlled conductive pathways, which are consistent with field evidence of wall deformation and seepage at the slope toe. Compared to single-method imaging, our multi-geophysical approach improves imaging resolution and reliability of interpretation for saturated zones and potential slip surfaces, providing an event-scale diagnostic for behaviors of post-rainfall slopes and a practical basis for remediation and early warning. Conceptually, this study advances the application of geophysical sensing to rainfall infiltration by establishing ERT, TEM, MASW, and AMT as a cohesive hydrogeophysical observatory for mapping water distribution and seepage in complex slopes.</p>