TO SQUASH: A lot of things.

Assets/Scripts/Game/Debris.cs

@@ -0,0 +1,40 @@
+using UnityEngine;
+
+public class Debris : MonoBehaviour
+{
+    protected Vector2 speed;
+
+    // Start is called once before the first execution of Update after the MonoBehaviour is created
+    void Start()
+    {
+        speed = new Vector2(Random.Range(-0.05f, 0.05f), Random.Range(-0.05f, 0.05f)).normalized * 0.05f;
+    }
+
+    // Update is called once per frame
+    void FixedUpdate()
+    {
+        transform.Translate(speed);
+    }
+
+    public void AnimationFinished()
+    {
+        Destroy(gameObject);
+    }
+
+    void OnCollisionEnter2D(Collision2D collision)
+    {
+        if (collision.gameObject.CompareTag("Wall"))
+        {
+            ContactPoint2D contact = collision.GetContact(0);
+            speed = Vector2.Reflect(speed, contact.normal);
+        } 
+        else
+        {
+            Physics2D.IgnoreCollision(
+                gameObject.GetComponent<Collider2D>(), 
+                collision.gameObject.GetComponent<Collider2D>(), 
+                true
+            );
+        }
+    }
+}