I think he means how to make the entire map visable, not so you can view the entire map at once.
[trigger:1:cb341323c8]Visibility - Create an initially Enabled visibility modifier for Player 1 (Red) emitting Visibility across (Playable map area)[/trigger:1:cb341323c8]
Use something like that, or this
[trigger:1:cb341323c8]Actions
Visibility - Disable fog of war
Visibility - Disable black mask[/trigger:1:cb341323c8]