Treason

Treason is a technology researchable at the Castle in Age of Empires II. It costs 400 gold and is available in the Dark Age. It is only available in the Regicide mode and replaces the Spies technology. Unlike spies, Treason reveals the position of the enemy king, and unlike all other technologies, Treason's effects are only temporary; players must research it repetitively to keep track of the enemy king's location. Treason is one of the most important abilities in Regicide; it tells players where to mount their offensives and to plan ahead.

Real Info
Treason is a crime against the state. In the context of the Middle Ages, treason is closely linked with kings since most governments in the middle ages were monarchies.