// Add this script to a Parent GameObject of the spawnPoints.
// Note: enemyPrefab will have an AI script attached which will already Tag the Player object  
// so it won't be needed here.

var spawnPoints : Transform[];  // Array of spawn points to be used.
var enemyPrefabs : GameObject[]; // Array of different Enemies that are used.
var amountEnemies = 20;  // Total number of enemies to spawn.
var yieldTimeMin = 2;  // Minimum amount of time before spawning enemies randomly.
var yieldTimeMax = 5;  // Don't exceed this amount of time between spawning enemies randomly.

function Start()
{
     Spawn();
}

function Spawn()  
{  
    for (i=0; i<amountEnemies; i++) // How many enemies to instantiate total.
    {
       yield WaitForSeconds(Random.Range(yieldTimeMin, yieldTimeMax));  // How long to wait before another enemy is instantiated.

       var obj : GameObject = enemyPrefabs[Random.Range(0, enemyPrefabs.length)]; // Randomize the different enemies to instantiate.
       var pos: Transform = spawnPoints[Random.Range(0, spawnPoints.length)];  // Randomize the spawnPoints to instantiate enemy at next.

       Instantiate(obj, pos.position, pos.rotation);  
    }  
}  

using UnityEngine;
using System.Collections;

public class SpawnEnemy : MonoBehaviour {
  public GameObject [] oenemy; // Массив мобов
  public Transform [] spawpoint; // их местоположение
  public float TimerSp = 15.0f; // Время таймера  

  // Use this for initialization
  void Start () {
   
   Spawn (); // вызываю функцию
   
  }
   
  // Update is called once per frame
  void Update () {
   if(TimerSp > 0){ // Чекаю условие
    TimerSp -= Time.deltaTime; // выполняем
   }else if(TimerSp <= 0) {  
       Spawn(); // вызываю спавн  
     }
  }

  void Spawn()
  {
   int i;
   GameObject obect;
   Transform pos;
   for (i=0; i<oenemy.Length; i++)  
   {
    obect = (GameObject) oenemy[Random.Range(0, oenemy.Length)];
    pos = (Transform) spawpoint[Random.Range(0, spawpoint.Length)];
    Instantiate(obect, pos.position, pos.rotation);

using UnityEngine;
using System.Collections;

public class SpawnEnemy : MonoBehaviour {
  public GameObject [] oenemy; // Массив мобов
  public Transform [] spawpoint; // их местоположение
  public int maxenemy = 10; // Маскимальное кол-во врагов
  public float TimerSp = 15f; // Время таймера  

  // Use this for initialization
  void Start () {
   
   Spawn (); // вызываю функцию
   
  }
   
  // Update is called once per frame
  void Update () {
    if(TimerSp > 0){ // Чекаю условие
    TimerSp -= Time.deltaTime; // выполняем
   }else if(TimerSp <= -1) {  
       Spawn();
     // вызываю спавн  
     }
  }

  void Spawn()
  {

   GameObject obect;
   Transform pos;
   int i;
   for (i=0; i<=maxenemy; i++)  
   {
    obect = (GameObject) oenemy[Random.Range(0, oenemy.Length)];
    pos = (Transform) spawpoint[Random.Range(0, spawpoint.Length)];
    Instantiate(obect, pos.position, pos.rotation);

     }
  }
}