How might i go about making a trail render that destroys people

I have figured out how to make it hit like the walls and stuff but im a noob at scripting so i cant figure out how to get it to hit the trail renderer because the trail renderer isnt like phisical but a wall is. Also how do i use OnControllerColliderHit() im sorry i just dont understand

I misunderstood your question. I assumed you were talking about something like a fireball with a tail where the head of the fireball is that you need to test. From this comment, you want any part of the line to be detected. That is a tail exists and you want a player who runs into the tail to be detected. Probably the easiest is to keep an array of Vector3 positions of the head of the trail renderer. I'd sample less frequently than every frame...5 or 10 times a second. Then you can do a Physics.LineCast() between the points to see if anything intersected. As a "noob at scripting" you may find this a bit challenging. I likely use something called a "circular list" implemented with Unity's build-in arrays and a head and tail index. Since the trail renderer is based on time, given the sample rate and the time, you will know how large the array needs to be. Note this will not detect edge hits, only something that intersects with the middle of the trail.

Think 'Tron Light Cycle' =]

Have a look at this : http://answers.unity3d.com/questions/285040/draw-a-line-in-game.html

Take a look at @alucardj 's link. The solution will work with the fringe as well as the center of the LineRenderer. I'm impressed at the links he's always posting.

Here is a bit of code that implements the simpler idea I had. It only works if the object passes through the longitudinal axis of the tail. Note you could add additional hit conditions or process multiple hits inside the Hit() function.

 #pragma strict
 
 var time : float = 2.0;
 var rate : int = 10;
 
 private var arv3 : Vector3[];
 private var head : int;
 private var tail = 0;
 private var sliceTime : float = 1.0 / rate;
 var hit : RaycastHit; 
 
 function Start () {
     arv3 = new Vector3[($$anonymous$$athf.RoundToInt(time * rate) + 1)];
     
     for (var i = 0; i < arv3.Length; i++)
         arv3[i] = transform.position;
     head = arv3.Length-1;
     StartCoroutine(CollectData());
 }
 
 function CollectData() : IEnumerator {
     while (true) {
         if (transform.position != arv3[head]) {
             head = (head + 1) % arv3.Length;
             tail = (tail + 1) % arv3.Length;
             arv3[head] = transform.position;
         }
         yield WaitForSeconds(sliceTime);
     }
 }
 
 function Update() {
     if (Hit())
         Debug.Log("I hit: "+hit.collider.name);
 }
 
 function Hit() : boolean {
     var i = head;
     var j = (head  - 1);
     if (j < 0) j = arv3.Length - 1;
     
     while (j != head) {
         
         if (Physics.Linecast(arv3[i], arv3[j], hit))
             return true;
         i = i - 1; 
         if (i < 0) i = arv3.Length - 1;
         j = j - 1;
         if (j < 0) j = arv3.Length - 1;
     }
     return false;
 }

Thanks ill try this out, here's a link if you want to see how far i have gotten on this game. http://www.youtube.com/watch?v=V4mNjj$$anonymous$$gsGQ