Heroes are special units in Age of Empires II. Unavailable in regular games, heroes typically refer to historical figures. As such, they are often featured in campaign scenarios. There, they are often must-survive units, i.e. their death means instant defeat. With The Conquerors, all heroes are immune to conversion and gain the ability to regenerate hit points. Heroes often have unique icons and sometimes even unique unit designs, and usually have good combat stats, making them very valuable in-game.