Schematic illustration of each EMD mode. Thin solid black lines in the background represent the magnetic field configuration, while the thick black line denotes the photospheric surface. Dashed and dotted black lines indicate the umbral and penumbral boundaries, respectively. Blue and red curves represent the wavefronts of the c₁ and c₂ modes, respectively. The cyan circle highlights the shock merging region. The dark red line near the penumbral boundary illustrates the leading shock front, where the preceding wavefront (red line) merges. Bidirectional arrows indicate the direction of oscillations: blue for c₁, red for c₂, purple for merged-shock oscillations, yellow for convection-driven kink oscillations, and navy for p-mode-driven kink oscillations.