ZONE OF CONTROL

Every unit exerts a Zone of Control into every adjacent square (but units in sea squares do not exert zones of control into land squares, nor vice versa).

Land units may not normally move between two squares in an enemy zone of control, with the following exceptions:
* Units may freely move into and out of bases.
* Units may freely attack any adjacent unit.
* Units may freely enter squraes already containing friendly units.
* Probe teams and units with the Cloaking ability may ignore this rule.

Air and Sea units exert zones of control, but are not affected by them.