Age of Empires: The Rise of Rome is an expansion pack for the real-time strategy game Age of Empires. It is based on the rise of the Roman Empire, and adds the Roman Empire and three other playable civilizations to Age of Empires. Gameplay-wise, the expansion introduced numerous interface tweaks, such as unit queuing, the ability to double click a single unit and highlight others of the same unit-type, balancing damage done by catapults, and the option to increase the population limit beyond 50 (only in multiplayer games). By installing the 1.0a update from 1999, it is also possible to use the period key to cycle through idle villagers. The Rise of Rome also features a new Roman architectural design, shared by all four new civilizations, the Romans, Palmyrans, Macedonians and Carthaginians. Four new researchable technologies have been added. Additional new features include five new units, four new random map types, and a larger map size option. Pathfinding for all units is also considerably improved. New music was composed for this expansion, which replaced the original score entirely. After the last official patch by the developer, the game's community continued the support by an own-made unofficial patch to address remaining issues and to improve compatibility with modern hardware and OSes.