Difficulty Levels

‘cooked_difficulty_levels’
Customize the difficulty levels.

Example 1:

// Add an "Extreme" level:
add_filter( 'cooked_difficulty_levels', 'custom_cooked_difficulty_levels', 10, 1 );
function custom_cooked_difficulty_levels( $levels ){
    $levels[4] = 'Extreme';
    return $levels;
}

Example 2:

// Remove "Beginner":
add_filter( 'cooked_difficulty_levels', 'custom_cooked_difficulty_levels', 10, 1 );
function custom_cooked_difficulty_levels( $levels ){
    if ( isset($levels[1]) ): unset( $levels[1] ); endif;
    return $levels;
}

Example 3:

// Create your own custom levels:
add_filter( 'cooked_difficulty_levels', 'custom_cooked_difficulty_levels', 10, 1 );
function custom_cooked_difficulty_levels( $levels ){
    return array(
        1 => 'Easy',
        2 => 'Normal',
        3 => 'Hard',
    4 => 'Impossible'
    );
}