Dealing Ranged Damage with Raycasting in Unity 3D

EnemyHealth.js

var health = 100;

PlayerHealth.js

var health = 100;

ShootFireball.js

#pragma strict

var fireballPrefab: GameObject;
var spawnLocation: Transform;

function Start () {

}

function Update () {
	//create a Vector3 representing the forward direction
	var forward: Vector3 = spawnLocation.TransformDirection(Vector3.forward) * 50;

	//draw debug ray straight ahead
	Debug.DrawRay(transform.position, forward, Color.green);

	//shoot fireball
	if(Input.GetButtonDown("Fire2")){
		var spell = Instantiate(fireballPrefab, spawnLocation.position, spawnLocation.rotation);

		//raycast - anything there?
		var hit: RaycastHit;													//create hit object to store raycast results
		if(Physics.Raycast(spawnLocation.position, forward, hit)){				//if raycast hits something...
			var enemy = hit.collider.gameObject;								//get the GameObject that was hit
			var eh = enemy.GetComponent(EnemyHealth);							//get the EnemyHealth component from enemy
			eh.health -= 10;													//decrease health by 10

			//change value on screen
			var ehDisplay = GameObject.Find("Enemy_HealthDisplay");
			var ehText = ehDisplay.GetComponent(GUIText);
			ehText.text = "Enemy Health: " + eh.health;
		}
	}
}

TakeDamage.js

#pragma strict

var waiting = false;
var waitUntil = 0;

function OnTriggerStay(){
	var enemyHealth = GetComponent(EnemyHealth);
	var ehDisplay = GameObject.Find("Enemy_HealthDisplay");

	if(Input.GetButtonDown("Fire1")){
		//decrease enemy health
		enemyHealth.health -= 10;
		print("Enemy took 10 damage.");

		//change value on screen
		var ehText = ehDisplay.GetComponent(GUIText);
		ehText.text = "Enemy Health: " + enemyHealth.health;
	}
}