Optional ReadonlyacyclicOptional Readonlyattributesfixed attributes, name -> value type
Optional Readonlycardinalityminimum and maximum number of children by tag
Optional Readonlychildrenallowed child tags; when omitted, any child is accepted
Optional ReadonlyopenWhen set, any attribute name is accepted on this tag and every value is
checked as this type. Open data maps need this: the keys of a movement
table ([movement_costs], [defense], [resistance]) are game-defined
terrain or damage-type ids, not schema-defined attribute names.
Optional Readonlyopenwhen true, children are accepted even though children is set
Optional Readonlyreftarget tag for declared ref attributes, or * for any id-bearing node
Optional Readonlyrequiredattributes required on every occurrence of this tag
ref attributes which must form an acyclic graph