The hot plasma filling galaxy clusters is susceptible to a convective MHD instability known as the MTI.
Understanding the implications of this convection has been surprisingly difficult, however; it depends
on both the large-scale evolution of the cluster and on the plasma physics of the gas. I will describe
a new set of "semi-cosmological" simulations which capture enough of the cosmic evolution of galaxy
clusters to reproduce their large-scale properties but still provide an idealized environment in which to
study cluster convection and its implications.