How to Instantiate Sprite Prefab C#? - [SOLVED]

Hello all, I have been struggling with what I thought would be a very trivial concept, and it has proven to be quite frustrating.

So, I am trying to create a simple 2D game right now in which you control a character that can shoot spells of some sort. Currently, I am having trouble instantiating prefabs of a fireball spritesheet.

I have used the sprite importer / editor to slice up my sprite sheet into appropriately-sized sprites.

I then dragged all of the sprites I planned on using onto to the Game screen, then dragged them all into the Prefabs folder so that their names turned blue and became prefabs.

I then have a script on an empty game object called SpellSpawner that has a public array of GameObjects called spells[] which I have set to 3. I dragged 3 of the prefabs I wanted to use into each individual game object spot in the list. However, whenever I try to call or instantiate an object from the list (e.g. spells[0]) it gives me a null reference error.

Could anyone help me understand what I am doing wrong? Here is my code: using UnityEngine; using System.Collections;

 public class SpellCast : MonoBehaviour {
     
 
     //reference to hero
     private GameObject hero;
     private HeroControl control;
 
     //array to hold particles for different spells
     public GameObject[] spells;
 
     void Start () {
         hero = GameObject.Find ("hero");
         control = (HeroControl) hero.GetComponent (typeof(HeroControl));
 
     }
 
     // Update is called once per frame
     void Update () {
         if (Input.GetButtonDown ("Fire1") && control.facing == "right") {
             GameObject spellBolt;
             spellBolt = Instantiate(spells[0], transform.position, transform.rotation) as GameObject;
             spellBolt.transform.position = transform.position;
 
         }
     }
 }

And here is a picture of the whole situation in Unity: