 <p>If you attach this script to <code>Water</code> particle, and you have a <code>Fire</code> particle, then in your water collision script</p> <pre><code>if (other.gameObject.name=="Fire") { Destroy(other.gameObject); // bonus effect for smoke particles // Instantiate(smokeObject, other.gameObject.transform.position, other.gameObject.transform.rotation); } </code></pre>