Spy (Age of Empires III)

The spy is a unit available from the church starting in the first age. It costs only coin, however it is fairly expensive, and costs 2 population spots. The spy moves very quickly, and has the stealth ability (although it can be seen at all time by the enemies explorer and town center). The spy is very good at scouting the enemy without them knowing, giving advanced notice on what they are building and when they will attack. The spy has a very low base damage, but huge multipliers against explorers and mercenarys. The spy can easily change the tide of a battle by coming in stealted, and unstealting and taking out enemy cannons and mercenarys.