The problem is that the "clone" variable is declared in Start, so it only exists in Start, and not in OnTriggerEnter. You have to make "clone" be a global variable instead of a local variable.

You're instantiating a prefab called "Clone" then later trying to Destroy "Clone". Problem is I THINK that what you need to do is to destroy the Clone(Clone) (as appears in Inspector when you play)

Make sure the prefab has a tag - e.g. name the tag "Clone". Then have:

Destroy(GameObject.FindWithTag("Clone")};

Get rid of the Destroy (clone); Destroy (gameObject) stuff you have etc and just have the above - see if that works??

Your problem is called variable scoping (what Eric5h5 said, and I voted up his answer for that). To clarify:

var prefab : Transform;  // this var is scoped to entire class

function Start () {

   // this var is scoped to ONLY the start function

   var clone  = Instantiate (prefab, Vector3(transform.position.x,
   transform.position.y,
   transform.position.z),
   Quaternion.identity);

}

So all you need to do is this:

var prefab : Transform;
var clone : GameObject; // now available for all functions

function Start () {
   clone  = Instantiate (prefab, Vector3(transform.position.x,
   transform.position.y,
   transform.position.z),
   Quaternion.identity);
}

Eric5h5 is correct.

You are declaring the variable twice by saying var clone= both as a statement and in the function. In the function just say clone = not var clone = .

I'm late but....

I've found a way to Do this and works for me.

I attach one Script in the prefab so when i Instanced this in other Variable....

i call to their self destruction function. obviously declare the variable global

/////////////////////

var instant = null; var pref : GameObject; //load in inspector , it has the script with the destroy function

function Start(){ { instant=Instantiate(pref,Vector3(0,2,0), Quaternion.identity); instant.selfDestroy();//in this example is created and destroy inmediatly }

function myDestroy(){//this is call when i need destroy instant { instant.selfDestroy(); }

so.....

//in instant attached Script

function selfDestroy(){ Destroy(gameObject);//SelfDestroy

}

//and Destroy only the Instant clone

Bye !! and luck