ofb/Assets/Scripts/ProjectileBehavior.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class ProjectileBehavior : MonoBehaviour
{

    public bool pinned = false;

    public void Explode()
    {
        Destroy(this.gameObject);
    }

    public void Pin()
    {
        this.gameObject.GetComponent<Rigidbody2D>().constraints = RigidbodyConstraints2D.FreezeAll;
        this.gameObject.GetComponent<BoxCollider2D>().enabled = false;
    }

    public void OnCollisionEnter2D(Collision2D col)
    {
        if (col.gameObject.tag == "wall" || col.gameObject.tag == "Player")
        {
            Explode();
        }
    }
}