Trigger For Chaning LOS (line of sight)

[XShooterX]

hi, im trying to make a spell but i cant find any type of trigger that changes a unit LOS(Line of sight). can someone help me?

 

[HorizonTal]

There aren't such triggers, if you don't need the cycle day-night, make the night permanent, then work adding or removing the ability Super-Sight, which allows the units to see during the night as during the daytime