Probing the development of galaxy clusters in X rays

The development of galaxy clusters is discussed basing on our Supermodel, that expresses in full the entropy-modulated, hydrostatic equilibrium of the intracluster plasma in the DM gravitational wells. We relate central entropy levels to energy injections by AGNs or deep mergers, and the outer entropy distribution to the accretion rates of DM and shocked intergalactic gas. We propose these to decline because of the cosmological slowdown in the outskirts growth at late cosmic times. Thus in addition to explaining the CC vs. NCC cores, we propose conditions leading to steep vs. shallow outer temperature declines, and outline related prospects for WFXT and IXO.