all stun weapons work like other guns, at first u got to lower health points of the target and then "kill it" stun it with the stun/rod or gun, both of them do very low dmg, thats why u got to use another marine to "soften up" the target, since most of my marines use heavy lazors,i shoot as many times as needed (minus one) and then use the stun gun once, lets say to kill an ortodok u have to hit him 6 times then do it 5 times and use the stun gun. its quite easy if u get used to it, most of the times i end up with 1 alien killed and 7 stuned.