Trigger activated by 1 unit only?

[NASFMike]

how can a trigger be set off by one unit and not anyone eles.
 

[macguba]

Group the trigger to the unit, as if he was a loon would wanted to be in the unit's group.    Now look in the On Activation box in the trigger - you will find new options.



Edit:   alteratively, if the loon in question is a member of a group, try setting the Activation box to Anybody present and write this in the Condition field:

loon1 in thislist