What you'll want is to make a Validator of type "Unit Compare Vital". Set the "Type" Field to "Fraction", the "Vital" field to "Life", the "Compare" field to "Less Than or Equal To", and the "Value" field to whatever fraction you want (e.g. 0.50 for 50% life, 0.25 for 25% life, etc.).
Then you add that validator to your behavior's "Validators (Disable)" field so that the behavior will only activate when the unit is below that fraction of life.
If anyone knows, id be thankful if you could post it here.
What you'll want is to make a Validator of type "Unit Compare Vital". Set the "Type" Field to "Fraction", the "Vital" field to "Life", the "Compare" field to "Less Than or Equal To", and the "Value" field to whatever fraction you want (e.g. 0.50 for 50% life, 0.25 for 25% life, etc.).
Then you add that validator to your behavior's "Validators (Disable)" field so that the behavior will only activate when the unit is below that fraction of life.
Hope this helps!
In reply to XiEntaj:
Will look into it tomorrow, but sounds good :)
Thanks for the fast reply!