In September 2011 NASA released a Request for Information on "Concepts for the Next NASA X-ray Astronomy Mission" and formed a Community Science Team to help study the submitted concepts and evaluate their science return relative to the goals identified by the 2010 Astrophysics Decadal Survey "New Worlds, New Horizons" report. After reading the responses and participating in a community workshop, the team identified a number of candidate mission concepts, including one combining advances in large-area precision optics with new X-ray microcalorimeter technology. However, the exact mission requirements (effective area, field of view, point spread function, etc) were not fixed. We will present a range of mission designs, describing the results of the NASA/GSFC Mission Design Lab study of one possible mission along with available deltas that would increase capability or decrease cost.
