Help with destroying spawned sprites

So I have 2 armies of randomly spawning sprites shooting at each other

But the problem is, when 1 of its kind dies, the whole army dies..

I need to simply break this instance

Im currently using..

For each [Enemy]          > Enemy Destroy

Enemy healthbar = 0

Any ideas guys? >__<

a simple .capx example would be most helpful

Try this

dl.dropbox.com/u/108799982/Capx%20Demos/RandomHealth.capx