Power spectra of EoR 21 cm signal brightness temperature and their different components. The a–d panels show ${\mathrm{\Delta }}_{\delta T_{\text{b}}}^2,\hspace{0.17em}{\mathrm{\Delta }}_{\delta \delta }^2$, ${\mathrm{\Delta }}_{x_{\text{HI}}{x}_{\text{HI}}}^2$, and $\left|{\mathrm{\Delta }}_{x_{\text{HI}}\delta }^2\right|$ respectively as a function of k at different stages of reionization. The e panel shows the redshift evolution of the 21 cm power spectrum at different scales. The f panel compares the redshift evolution of ${\mathrm{\Delta }}_{x_{\text{HI}}{x}_{\text{HI}}}^2,\hspace{0.17em}{\mathrm{\Delta }}_{\delta \delta }^2$, and $\left|{\mathrm{\Delta }}_{x_{\text{HI}}\delta }^2\right|$ at k = 0.1 h Mpc⁻¹. The power spectra correspond to our fiducial GRIZZLY EoR scenario as shown in Fig. 1.