  We present results from deep Chandra and XMM-Newton observations of the
relaxed X-ray luminous galaxy cluster Abell 2204. We detect metallicity
inhomogeneities in the intracluster medium on a variety of distance scales,
from a ~12 kpc enhancement containing a few times 10^7 Msun of iron in the
centre, to a region at 400 kpc radius with an excess of a few times 10^9 Msun.
Subtracting an average surface brightness profile from the X-ray image yields
two surface brightness depressions to the north and south of the cluster. Their
morphology is similar to the cavities observed in cluster cores, but they have
radii of 240 kpc and 160 kpc and have a total enthalpy of 2x10^62 erg. If they
are fossil radio bubbles, their buoyancy timescales imply a total mechanical
heating power of 5x10^46 erg/s, the largest such bubble heating power known.
More likely, they result from the accumulation of many past bubbles.
Energetically this is more feasible, as the enthalpy of these regions could
combat X-ray cooling in this cluster to 500 kpc radius for around 2 Gyr. The
core of the cluster also contains five to seven ~4 kpc radius surface
brightness depressions that are not associated with the observed radio
emission. If they are bubbles generated by the nucleus, they are too small to
balance cooling in the core by an order of magnitude. However if the radio axis
is close to the line of sight, projection effects may mask more normal bubbles.
Using RGS spectra we detect a FeXVII line. Spectral fitting reveals
temperatures down to ~0.7 keV; the cluster therefore shows a range in X-ray
temperature of at least a factor of 15. The quantity of low temperature gas is
consistent with a mass deposition rate of 65 Msun/yr.
