:state=x,
shotdamage=x:dosomething...
very easy to get a reaction from a npc if he gets shot a specific damage. its also possible to cause different reactions in doing these in more lines and set different x.

10dmg = jumps in the air and gargles
20dmg = running in circles and doing chicken sounds
30dmg = running to the next wall banging his head against it
40dmg = shouts "attention ladies and gentlemen, please fasten your seatbells we are ready to take off"
50dmg = runs towards player and explodes in a 1000dmg fireball up to the sky.
no problem.
edit: now i see the above i think i will write that script, sounds funny^^