"NullReferenceException: Object reference not set to an instance of an object" with instantiate C#

This must be something super simple that I'm missing but I couldn't find it for the life of me. I have pasted my entire script, but the error is on line 48 when I try to add force to the instantiated object. The object has a rigidbody attached. using System.Collections; public class slimy : MonoBehaviour { public Rigidbody coin; float hp = 10; float defence = 1; public GameObject[] drops; public int[] droprate; public int mincoin = 1; public int maxcoin = 3; public Transform coinpos; public float moneyspread = 100; void OnCollisionEnter2D(Collision2D coll) { hitarrow (); deathcheck (); } void hitarrow(){ float initial = playerattack.calculatedmg ("arrow"); float dmg = initial / defence; hp -= dmg; Debug.Log ("Damage: " + dmg); } void deathcheck(){ if (hp <= 0) { drop(); Destroy (gameObject, 0.001f); } } void drop(){ for(int i = 0; i < (Random.Range (mincoin, maxcoin)); i++){ float coinforce = Random.Range(100f, 350f); float coinrot = Random.Range(0f, 360f); coinpos.localRotation = Quaternion.Euler(0, 0, coinrot); coinpos.position = transform.position; /* Rigidbody2D shot; shot = Instantiate(coin, coinpos.position, coinpos.rotation) as Rigidbody2D; shot.velocity = transform.TransformDirection(Vector2.up * coinforce); */ Rigidbody clone; clone = Instantiate(coin, transform.position, coinpos.rotation) as Rigidbody; clone.velocity = transform.TransformDirection(Vector3.up * 10); } } }