The Japanese are primarily an offensive civilization geared towards infantry. The Japanese work well on land maps but fare much better on maps with large bodies of water since it is the only type of map where their bonus on Fishing Ships can be used effectively.
Their infantry attack faster than those of other civilizations giving their infantry an edge in large battles. The Japanese unique unit is the Samurai, a formidable infantry unit that has a fast attack and attack bonus versus other unique units. This is a big advantage in the late game when most civilizations rely heavily on their unique units. Civilizations that rely on infantry units will also be at a disadvantage against the Japanese due to the faster attack speed of Japanese infantry. They also have an effective navy, with fishing ships gaining extra hitpoints and their Galleons gaining more line of sight. They lack the Heavy Demolition Ship, but this need not be a negative since the resources would be better spent on Galleons or Fishing Ships. The Japanese also have full archer technologies.
In contrast to their infantry they have fairly weak cavalry, missing the Paladin and Hussar upgrades. This is in addition to not having the Camel. They also lack the Bloodlines upgrade, putting them at a disadvantage in cavalry battles. The fact that their Spearmen have a faster attack and can kill cavalry units even faster than normal somewhat makes up for this but they still lack the speed of the Camel so are less effective when chasing fleeing cavalry.They lack a lot of late-game economic technologies: Gold Shaft Mining (which was added for them in The Forgotten), Stone Shaft Mining, Guilds and Crop Rotation. Their siege weapons are also average since they lack the Siege Onager and Siege Ram. Although their unique unit is good, it is still not good against many unique units, like Longbowmen, Cataphracts, and Mangudai.
Japanese are a rare mix: An offensive civilization with a strong early economy. They have one of the strongest Feudal Age rushes (flushes) in the game as a result of their infantry attack speed bonus in the Feudal Age. The wood saved from a Mill, Mining Camp and Lumber Camp totals to enough for an effectively free Dock. With this dock, they are able to make powered-up Fishing Ships, even while advancing to the Feudal Age. This gives their economy a large boost to produce extra troops in a flush.
However, just because Japanese have a good flush doesn't mean they need to use it. They also have a strong Castle Age and even Imperial Age. Arguably the best Champions in the game (with the possible exception of Aztecs, or Vikings if they're being used for cannon-fodder, or the Slavs ), powerful Samurai, powered-up Trebuchets, and a strong navy allows them to hold their own even into the Imperial Age. Whenever possible, a Japanese player must use Fishing Ships to boost his economy.
A fishing boom Fast Imperial often benefits the Japanese in team games where they have time to build up. Then the Japanese must train primarily Champions, Halberdiers, Samurai and Arbalests depending on the situation. Champions are general force units, cheap and powerful. Halberdiers easily ward off cavalry, and require no gold. Samurai keep away melee-based Unique Units, with the exception of the Cataphract. Teutonic Knights can deal with Samurai to an extent, but are not cost effective in the least. Arbalests provide range support for melee units. Japanese Trebuchets are also among the best in the game, firing significantly faster, and packing and unpacking in an extremely short period of time.
Japanese should almost always take over the sea so as to reap the full benefits of their Fishing Ships. Fishing Ships can even be used as cannon-fodder if the opponent forgets to aim his weapons himself, as they cost no gold and are reasonably well-armored, and have nothing to do after they finish fishing.
Defensively, Japanese are more or less average. Their Trebuchets do work excellently in conjunction with Castles when defending.
The Japanese will have a hard time with civilizations that specialize in gunpowder such as the Turks, due to Turks' Hand Cannoneers, with a bonus against infantry, will decimate Japanese's infantry. The Japanese are a tougher opponent to the Goths, since Japanese's infantry is of higher quality.
Strategy changes in The ForgottenEdit
The new Japanese castle age tech Yasama allows their towers to fire extra arrows, giving them an offensive edge. However, the benefit of this advantage is minimal, as the Japanese still lack Architecture, Heated Shot and Bombard Towers. That being said, the Yasama allows the Japanese to do a tower rush strategy, as the towers firing extra arrows combined with Arbalests or Hand Cannoneers garrisoned in the towers with Trebuchets or Capped Rams can add a lot of pressure in the enemy player. The Japanese now also have access to Bloodlines, improving their cavalry and giving them access to fully upgraded knights in the Castle Age as well full Heavy Cavalry Archer upgrades. Their new ability to research Gold Shaft Mining slightly improves their economy as well.
Strategy Changes in The African KingdomsEdit
The cost of Yasama has been slightly reduced, allowing the Japanese to effectively forward towers earlier. The introduction of the Arrowslits technology further improves the power of Japanese towers, allowing fully upgraded towers to decimate all but the most heavily armored enemies. The introduction of the Arson technology allows Japanese infantry to inflict even more damage to buildings, and combined with their natural bonus against buildings and the Japanese increase in attack speed, turns their Champions into human siege weapons.
As an infantry civilization, the Japanese benefits greatly from team bonuses that improve infantry, like the Goths (more production speed for the barracks) and the Italians (enables them to create the condottiero at the barracks).
Also, as a Civilization that has several naval bonuses, including their team bonus, the Japanese makes great synergy with other naval civilizations, such as the Byzantines, Vikings, Saracens, Berbers, Italians, Portuguese, and Malay.
Even in terms of gunpowder units, both the Japanese and the Vietnamese received the component the other party really need, apart from the fact the former received adequate info for their infantry rushes, plus Imperial Skirmishers and fire support from Bombard Cannons to screen Samurai and other infantry from enemy archers while the latter receive vigilant, well-scouting Galleys, plus combined-arm support from the former's superb navy, infantry with Samurais as the core, Hand Cannoneers and Trebuchets with the Kataparuto upgrade.