Three kinds of bullets are firing, bomb breaks the wall

Assets/Scripts/Damagers/DamagerBase.cs

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+using UnityEngine;
+
+public class DamagerBase : MonoBehaviour {
+	public int value = 1;
+}

Assets/Scripts/Damagers/DamagerBase.cs.meta

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Assets/Scripts/Damagers/ExplosionDamager.cs

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+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+public class ExplosionDamager : DamagerBase {
+	//simply causes damage and then disappears
+	void Awake() {
+		StartCoroutine (DestroyAfter (0.5f));
+	}
+
+	IEnumerator DestroyAfter(float delay) {
+		yield return new WaitForSeconds (delay);
+		Destroy (gameObject);
+	}
+}

Assets/Scripts/Damagers/ExplosionDamager.cs.meta

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Assets/Scripts/Damagers/FireDamager.cs

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+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+//shootable
+public class FireDamager : DamagerBase {
+	void OnTriggerEnter2D(Collider2D collider) {
+		if (collider.gameObject.GetComponent<FireDamager> () == null) { //pass through other instances of self
+			Destroy (gameObject);
+		}
+	}
+}

Assets/Scripts/Damagers/FireDamager.cs.meta

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Assets/Scripts/Damagers/IceDamager.cs

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+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+//shootable
+public class IceDamager : DamagerBase {
+	void OnTriggerEnter2D(Collider2D collider) {
+		if (collider.gameObject.GetComponent<IceDamager> () == null) { //pass through other instances of self
+			Destroy (gameObject);
+		}
+	}
+}

Assets/Scripts/Damagers/IceDamager.cs.meta

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Assets/Scripts/Damagers/WindDamager.cs

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+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+//shootable
+public class WindDamager : DamagerBase {
+	void OnTriggerEnter2D(Collider2D collider) {
+		if (collider.gameObject.GetComponent<WindDamager> () == null) { //pass through other instances of self
+			Destroy (gameObject);
+		}
+	}
+}

Assets/Scripts/Damagers/WindDamager.cs.meta

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