Chi kai ri
If the Ninja managed to intercept a message between the enemy lord and his allies or relatives, he would forge the message and send it on its way again. He may have succeeded in completely intercepting and controlling the two-way correspondence. In this way, he managed to sow distrust and hostility between allies.
With this tactic, the Ninja invaded enemy territory, causing confusion and spreading fear and terror. He foresaw the enemy’s troop movements and immediately countered them. Or he spread false rumors, encouraged malcontents to revolt and riots, set fire to strategically important positions, and sowed distrust among the soldiers. He stole horses, weapons, and food or rendered them useless. If the enemy wanted to enter a village, he would already run ahead and spread panic among the inhabitants.
If the enemy left his camp, the Ninja took this chance and sneaked into the camp. He sabotaged important facilities in the camp, spread panic among the remaining guards, and opened the gates to his troops.
The Ninja could also kidnap key figures to enforce his terms. He blackmailed key figures into serving him or the kidnapping victim would be executed.
With this tactic, the Ninja sneaked into the enemy camp and pretended to be an ally there. Of course, this required that the Ninja was already known and well versed in the area.
With this tactic (moon in the water) the Ninja staged a diversionary maneuver. A squad of Ninja or part of the regular army launched a mock attack on one point of the fortress. While everyone rushed to the threatened spot, the Ninja climbed over the wall at the unattended spot.
With this tactic, the Ninja took on the appearance of a defenseless and unsuspecting person. He disguised himself as a beggar, cripple, blind, deaf or deaf-mute and tried to find shelter in the castle. He could also get into the castle with jugglers or traders.