Context. JWST has revealed galaxies at z > 10 with extremely blue UV-continuum slopes approaching βUV ≲ −2.4, and low inferred dust contents. At similar redshifts, JWST and ALMA reveal dusty massive systems reaching βUV ≳ −1. Aims. We aim to explain blue monsters and red monsters at z ≳ 10 as different outcomes of supernova dust retention in clustered star-forming systems and connect this bimodality to dusty massive galaxies at z ≃ 6–7. Methods. We model dust removal in a cluster-dominated regime through cloud-scale mechanical blowout followed by breakout from stratified high-redshift disks. The shock-processed dust mass retained in the UV-attenuating layer is converted into a UV-continuum slope using absorption opacities derived from 3D hydrodynamical simulations of clustered supernovae in porous molecular clouds. Results. In compact, gas-rich galaxies, efficient cloud blowout and disk breakout reduce the retained dust fraction to blue-monster levels, yielding βUV ≲ −2.4. Larger stellar masses increase the retained dust column and produce red-monster-like systems with βUV ≳ −1.5, reaching βUV ≃ −0.5 when radiative losses weaken large-scale driving. Conclusions. The transition depends on whether clustered-supernova ejecta cross both the natal cloud and the galactic gas layer. Supernova dust production, shock processing, radiative losses, and mechanical venting can jointly explain UV-bright dust-poor galaxies and red dusty massive systems across 6 ≲ z ≲ 14.