Fe K band stacked spectrum for 27 MIPS (24 μm)-detected objects (black solid squares) and 33 non-detected objects (red open circles) from the ZH subset (Table 3, Type II objects at z > 2). The stacked spectrum of the MIPS-detected objects shows much stronger line emission and these objects are a dominant Fe K source in the ZH stacked spectrum of Fig. 11f. In particular, Fe xxvi appears to come only from the MIPS-detected objects.