I'm trying to create a Xel'Naga Tower in the middle of a melee map that offers vision to all players. Is there a way to do this without needing a unit to control the tower? Just have the tower offer vision to everyone? I'm not the greatest with this stuff regarding triggers and modifying units.
Alternatively if I could turn off Fog of War for a certain portion of the map and have it be visible to all players, that would be a perfectly acceptable alternative to modifying a unit.