Only two things I can think his action does is make something twice as strong (standard kill becomes unbockable?) or it replenishes one-shot abilities.
Nothing really changes if it's the former (afaik), but the possibility of replenishing one-shot abilities would do something. If he hits Cat5, Cat5 gets a day kill again (which has an obvious target). If he hits me, I get the one-shot abilities I used back.