By virtue of their large mass and deep gravitational potential well, galaxy clusters are filled with low-density but extremely hot weakly-magnetized plasma that emits X-rays. Many astrophysical processes, including feedback from supermassive black holes, mergers and large-scale structure evolution, are imprinted on this hot intracluster gas. Understanding these processes is crucial for, e.g., cosmological simulations that heavily depend on the assumptions built into their models, especially on small scales. The next fundamental frontier in the studies of galaxy clusters is measuring gas velocities and related microphysics. I will present some of our recent efforts toward understanding a full dynamic picture of the ICM, from cluster core regions to outskirts and from micro to macro scales. I will show observational constraints on transport properties of the ICM that are important for sustaining and dissipating gas motions, recent updates on feedback-driven gas motions, and high-resolution numerical studies of mergers-driven physics in cluster outskirts. I will finish my talk by reviewing near- (and more distant-) future X-ray missions and related new science.