How to treat prefabs respectively?

Hi lads, I’m new to Unity. My program is a FPS game. I have a enemy prefab and this is the js code:

var bloodOut : GameObject;
static var enemyHP : float = 100;

function Start () {
	Target = Camera.main.transform;
}

function Update () {
	if(enemyHP <= 0){
		Destroy(gameObject);
	}
}

I use ray-cast to detect if hits the enemy. Here is the code to generate the prefab:

function Start () {
    	enemy = Instantiate(enemy, Vector3(75.47046, 10.30222, 63.87109), Quaternion.identity);
    	//enemy = Instantiate(enemy, Vector3(85.47046, 10.30222, 63.87109), Quaternion.identity);
}

My enemy prefabs have a tag name “enemy”.

if(bulletHole1 && hit.transform.tag == "enemy"){
    			Instantiate(bloodSplat, hit.point + (hit.normal * frontHit), Quaternion.LookRotation(hit.normal));
    			enemy.enemyHP -= 5;
    		}	

This is all working good.
BUT,
when I release the comment to generate another enemy prefab, the problem comes. If I shoot one prefab then all prefabs dead. I know it’s because the HP variable is 0. But how to fix this problem? How can I separate the HP variable of all prefabs? I’m new to Unity, please tell me a little bit more details. Thanks!

Don’t use static variables. Static means there can only be one instance of that variable, no matter how many prefabs you have.

so first off dont have the variable as static.
then in your if (bullethole… statement
use hit.gameObject.GetComponent("scriptName").enemyHP -= 5;

or something like that
assuming you have that first script attached to each enemy