Overhead icons?

[mickmca]

Is there a place that explains the various icons that appear above the symbols for people or buildings? I assume the plus sign over military people mean they are "advanced." But what is the new "heart with a green plus" over enemy buildings, and what is the "hammer and tongs" that pops up over one's own buildings?

[sanderd17]

Those icons mean the units (or buildings) are affected by an aura. Specifically by the aura caused by the unit or building you selected.

F.e. if you select the temple, all units close enough to be in its healing aura will show the green plus. Details about the aura can be read by hovering the icon of the temple.

Note that not all auras are range-based (some or global or even something else), and auras may also affect allies or enemies (in a good or bad way).