  As various property studies continue to emerge on high entropy and
entropy-stabilized ceramics, we seek further understanding of property changes
across the phase boundary between \enquote{high-entropy} and
\enquote{entropy-stabilized}. The thermal and mechanical properties of bulk
ceramic entropy stabilized oxide composition
Mg$_{0.2}$Co$_{0.2}$Ni$_{0.2}$Cu$_{0.2}$Zn$_{0.2}$O are investigated across
this critical transition temperature via the transient plane-source method,
temperature-dependent X-ray diffraction, and nano-indentation. Thermal
conductivity remains constant within uncertainty across the multi-to-single
phase transition at a value of ~2.5 W/mK, while the linear coefficient of
thermal expansion increases nearly 24 % from 10.8 to 14.1 x 10$^{-6}$ K$^{-1}$.
Mechanical softening is also observed across the transition.
