The juggernaut is the first boss you face in kingdom rush. He ha high hp and has the capability to spawn golem heads to attack you which distracts your towers and may cause them to ignore the juggernaut. It shoots missiles that can target any soldier but soldier must be at least 4 towers away to be targeted. Beafore the final wave construct at least lvl 2 towers on each strategic point to prevent golem heads from leaking through your defenses.