Kingdom Rush  Kingdom Rush is a tower defense game developed by Ironhide Game Studio and published by Armor Games, released as a free flash browser game on July 28, 2011, on the iPad on December 19, 2011, on Android in May 2013, and a Unity port in January 2014 via Steam. A sequel, "Kingdom Rush: Frontiers", was released on June 6, 2013. The third installment of the franchise, "Kingdom Rush: Origins", was launched on November 20, 2014. It was released on PC on October 18, 2018. On November 22, 2018, Ironhide Studios released a new sequel, "Kingdom Rush Vengeance", in which the player plays as Vez'nan's servant, helping him regain his throne. "Kingdom Rush" is a real-time tower defense game set in a medieval fantasy setting. Each level presents a pre-determined path with empty slots all around, called 'Strategy Points', where the player can build towers. There are four types of towers to choose from : Mages, Archers, Barracks, and Artillery, each costing a certain amount of money to build and upgrade. At the beginning of each level, the player gets some money in order to build the first towers. As enemies begin to emerge from one end of the path, the towers must be able to kill them before they reach the other end of the path (defence point). The player will also rely on a few spells and heroes (with cool-downs) to help the towers. Killing enemies generates money, which can readily be used to build and upgrade towers. Another way to earn money is to call enemy waves early, which also reduces cool down time of spells. Money is also earned by selling built towers or having an enemy reach the defence point. When an enemy gets there, the player loses 1-20 lives depending on the enemy. There are 18 levels in total and 48 different types of enemies that one will encounter throughout the levels. Completing a level for the first time gives the player 1-3 stars. These stars can be used to unlock passive upgrades that improve the effectiveness of the various towers and spells. After completing a campaign level with 18 or more lives remaining (out of 20), the player earns 3 stars and the Heroic Mode and Iron Challenge are unlocked for this level. These are more challenging modes that take place on the same path and impose various constraints. In these modes, the player will only be given one life, so any enemy surviving to the defence point triggers a failure.