Drill is a technology in Age of Empires II: The Conquerors that is unique to the Mongols and can be researched at the Castle once the Imperial Age is reached. Once researched, it allows Siege Workshop units to move +50% faster.
Drill allows Siege Workshop units to move significantly faster, making the Mongol army one of the most agile in the game. Siege Rams fully garrisoned with infantry can move just as fast as a Dark Age Scout Cavalry (and therefore faster than most foot soldiers). A Siege Tower filled with infantry becomes the second fastest land unit in the game (with a speed of 1.7 when fully garrisoned), only behind the Cuman Hussar.
|“||One of the secrets to the great success of the Mongols was their great discipline in battle. Where more civilized armies of the time had complex structures of hierarchy and traditions, the Mongols countered with endless hours of practice on the plains and hunting grounds. The speed at which Mongol armies could move and strike bewildered the more ponderous and heavily equipped armies they often fought.||”|
|—The Conquerors manual|