Optional Readonlycan_whether it can recruit, i.e. is a leader; a missing value reads as false
ReadonlyidOptional Readonlynameits own name, when it has one
Optional Readonlyroleits role/function, e.g. leader or courier
Readonlysidewho it fights for; sides are compared by name, so allies share one
Optional Readonlytypeits unit type, when the game's world has one (a Wesnoth [unit] type=)
ReadonlyxReadonlyy
A subject as a score view needs it: the game's own handle, its side, and where it stands.