Left panel: Evolution of mean circularity parameter, ⟨ϵ_circ⟩=⟨J_z/J_circ⟩, with cosmic time (t) and corresponding redshift (z) for Amaryllis. The horizontal dashed line indicates the disk threshold ($1/\sqrt{3}$, Simons et al. 2019), while the shaded region highlights the triple merger phase. Right panels: Velocity (v) and velocity dispersion (σ) maps of the gaseous disk in [C II] and [O III] emission, showcasing the early gaseous disk properties at z ≃ 11 in FIR emission lines observable with ALMA at these redshifts.