Trying to spawn random falling rocks, can't figure out why it's not working. Help would be appreciated!

I am making a 2D adventure game. In one level, the player is faced with a chamber full of rocks that are falling from above screen height and down to the ground the player is on, and kills the player if one hits him.

The problem I am having is the delay between rock spawns. I tried an IEnumerator function called after every rock spawn, but it doesn’t seem to work. Unity just freezes when I run the code.

Here is my full code:

using UnityEngine;
using System.Collections;

public class SpawnRocks : MonoBehaviour {

    public static Transform rockSpawn;
    public GameObject[] rocks;

    int spawnSpot;

    void Start () {
	void Update () {


    void SpawnRock() {
        //change up spawn position of rocks a bit
        spawnSpot = Random.Range(-1, 8);
        //pick a random rock prefab from our array of prefabs, copy it to the new theRock object
        GameObject theRock = rocks[Random.Range(0, rocks.Length)];

        //spawn theRock
        Instantiate(theRock, new Vector3(transform.position.x + spawnSpot, transform.position.y, transform.position.z), Quaternion.identity);
        //give it a random direction and velocity
        theRock.GetComponent<Rigidbody2D>().velocity = ((Vector2)Random.onUnitSphere).normalized * Random.Range(5, 10);

        //destroy theRock after 2 seconds
        Destroy(theRock, 2f);

        //wait for a random amount of seconds

        //spawn another rock

    public static IEnumerator Wait() {
         yield return new WaitForSeconds(Random.Range(.2f,.5f));

If I delete the recursive SpawnRock(); call at the bottom, and take out SpawnRock(); from the Start function, then add it to just Update(), rocks just continually spawn until the game lags out. I know it must be something wrong with my Wait function, but I cannot find out what.

Any help is much appreciated! Thank you in advance.

You should use StartCoroutine in combination with WaitForSeconds to create a continuation for x seconds, currently as you stated it will just keep going over and over. It’s better to use the Update/FixedUpdate methods to execute these functions, but either way, StartCoroutine is your friend. Optionally InvokeRepeating

I think the problem is here:

         //wait for a random amount of seconds

This does not actually wait for a number of second before moving to the next instruction. You can use it to get a similar behavior with coroutines.

Here’s an example of recursion made using coroutines in Unity.

And here is some unity documentation for the coroutine thing, with a bunch of examples in there.