Is it essentially VITAL for it to be a gamelogic
Because a trigger would be much easier,
And you CAN move triggers around in game if that is the primary concern
If So…
Create a trigger to the specification you want, call it killtrigger
use the following script code
Killtrigger.sqs
#top
_units = (list killtrigger)
"_x setdammage 1" foreach _units
~1
goto "top"
However,
I think you can just set the trigger to repeatedly and put in the On activation field
"_x setdammage 1" foreach thislist