Ninjas are infantry units that are very effective against heroes and mercenaries. Ninjas themselves are mercenaries, so are easily countered by Spies. The Ninja can also use Stealth Mode, which can be detected by an Explorer or Town Center (or other units or buildings).
The Ninja differs from the Spy in that it is classified as a mercenary, in contrast to the Spy, making the Spy very effective against Ninjas. The Ninja also has much higher cost, slightly less speed, much lower Line of Sight and much lower multipliers, but it has more hit points and much higher base damage and siege damage. Ninjas also take up 4 population per unit, despite only costing 200 coin, whereas Spies take up only 1 population per unit, despite costing 125 coin. Ninjas are slightly more deadly against mercenaries, but less effective against heroes, and are far less useful for scouting. Exclusively, Ninjas have multipliers against native warriors.
As is the case with Spies, Ninjas are not cost effective against any units other than mercenaries and heroes. However, they do much better against normal units than Spies do, because of their higher base damage. This makes them more well-rounded than Spies. Ninjas are classified as heavy infantry and infantry, making them especially vulnerable to light infantry, counter-skirmishers, and artillery.
The Ninja also has worse accessibility than Spies, as Spies are always available from the Church/Mosque from the Commerce Age onward, can be sent from the Home City by European civilizations, while the Ninja can sometimes be trained at the Saloon/Monastery, or sent with Home City shipments by certain civilizations.
Ninjas are very useful in the third and fourth scenarios of the Chinese campaign (by choosing Japanese Mercenaries at the Consulate) because most enemies on these maps (namely, Aztec Jaguar Warriors and Aztec Eagle Warriors) are classified as native warriors, which the Ninja has bonuses against.
Ninjutsu-Zukai[]
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Japanese assassin. Highly effective against mercenaries, Explorers, War Chiefs, and Monks.
Infantry and shock infantry train time -40% (also +2 Uhlans for the Germans; +1 Villager for the Indians)
Outlaw Combat
Outlaws and mercenaries get +15% hit points and attack (also upgrades Filibusters to Veteran for Baja California; costs 750 coin for Baja California, Hungary, and Revolutionary Mexicans)
"Liberation March" is available to the Mexicans and Spanish.
"Fencing School" is available to the Europeans (except the French, Maltese, Ottomans, and Spanish) and Indians.
Consulate units' train time -50%; Consulate technologies' cost -40% (-300 export for Brigades) and research time -50% (except for Brigades)
Bakufu
Daimyo and Shogun Tokugawa get +5% speed, +10 Line of Sight and train units 15% faster; land military unit train time -20%, artillery and banner army train time -10% instead
The General, Minutemen, and heavy infantry get +15% hit points and attack
Poker
Ships 13 random mercenaries; up to 3 random mercenaries available at Saloon; costs 3,500 coin
Indiana Mobilization
Ships 1 Carbine Cavalry for each shipment sent so far this game including this one; unit train time (except Heavy Cannons), technology research time, and age-up time -10%; costs 250 food, 250 wood
Shrouded by the mists of time, the exploits of the ninja continue to fire imaginations across the globe. During the turbulent years of Japan's sixth and seventh centuries, a secret class of warrior priests emerged. Rulers of opposing factions came to value the ninja for their skills in stealth, combat, and espionage.
As the centuries passed, the legendary powers of the ninja grew: invisibility, shape-shifting, flight; even the ability to pass through solid walls. Modern filmmakers blend historical fact with ancient myth to fashion a portrait of a warrior class that continues to fascinate and terrify.
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Gallery[]
An in game Ninja
Ninja siege attack
Ninjas in action
A Ninja in the Stealth mode
In-game Ninja in the Definitive Edition
Ninja in the Stealth mode in the Definitive Edition