Integrated kinematic diagnostics of Amaryllis during its post-merger starburst phase at z ∼ 10.4. Main panel: Integrated [O III] 88 μm spectrum from a face-on orientation, highlighting a prominent narrow component tracing star-forming gas near systemic velocity, and a broad, blueshifted wing indicative of ionized outflows. The overlaid two-Gaussian fit separates these components, with residuals shown in the bottom subplot. The inferred outflow velocity is $v_{\mathrm{outflow}}\simeq 258{\mathrm{km}\mathrm{s}}^{-1}$. Inset panel: Spatial distribution of [OIII] emission in the edge-on projection, revealing extra-planar ionized gas consistent with a large-scale outflow.