That can be accomplished using a (Boolean) variable and a condition, E.G.
Begin Boolean Compare : [>turretsActivated] Equals False
Say, 'Turrets activated'
Else
Say, 'Turrets deactivated'
End Condition
Set Boolean [>turretsActivated] to Toggle
Make sure the condition and the "Set a True/False (Boolean) Value" action have the "Evaluate 'Not Set' as false" option checked.