 <p>As I see it you have a couple of alternatives. One of them is: </p> <p><strong>CUBE object</strong></p> <ul> <li>set a <code>boolean</code> variable on your cubes. <code>boolean hasBeenHit</code> or similar. This starts att <code>false</code>. </li> <li>Give the cube a <code>OnTriggerEnter()</code> where it sets the <code>hasBeenHit = true</code>.</li> <li>Make a public getter for <code>hasBeenHit</code>.</li> </ul> <p><strong>Ball object</strong></p> <ul> <li>In <code>OnTriggerEnter(Collider other)</code> check if <code>other</code> is a cube.</li> <li>If it is a cube, check if its <code>hasBeenHit</code> is <code>true</code> or <code>false</code>.</li> <li>If it is <code>false</code>, increment <code>count</code></li> </ul>