carmack-featured-content-amount.php

<?php
/**
 * Plugin Name: Change Carmack Featured Content Quantity.
 * Plugin URI: https://prothemedesign.com
 * Description: Change the number of posts that appear in the Carmack slider to 1.
 * Author: Ben Gillbanks
 * Version: 1.0
 * Author URI: https://prothemedesign.com
 * Text Domain: carmack
 */

function carmack_slider( $params ) {
	$params['max_posts'] = 20;
	return $params;
}
add_filter( 'carmack_featured_content', 'carmack_slider' );