Don't let the creeps complete their path. Do that by building defense towers along the way. Manage and upgrade them to get to higher levels. You have 6 types of towers to choose from once you have enough gold.
It all starts in the midst of civil unrest in the nation of Veidar. The duchy of Valis is rising against the kingdom with Duke Dunkeld leading the enemy armies. However, behind the enemy lines lurks something dark and evil..