Watch this walkthrough video of the Castle Defense game! The aim of Castle Defense is simple: you need to defend your castle against a legion of terrifying enemies who are trying to storm it. You’ll need to cast spells, destroy your enemies and increase your magical powers as you make your way through the increasingly difficult stages. It’s your job to protect the kingdom, so you need to become as powerful as possible to keep your people safe. You’ll also have to be quick, because your enemies come towards you at high speed.