Innin is a level 40 job ability for Ninjas in Final Fantasy XI. It reduces enmity generation and impairs evasion and grants a bonus to accuracy, critical hit rate, and Ninjutsu damage when striking target from behind for a duration of 5 minutes. It can be recast every 5 minutes and shares the timer with Yonin, so only one can be used at a time. Enmity decrease is approximately -20%, decaying to -10% over the duration. Critical hit bonus is approximately +30%. The bonus will apply to ranged attacks. Magic Attack Bonus increase is approximately +30% at start, decaying over time.
It increases the damage of Mijin Gakure when behind the enemy, as if it were a Ninjutsu spell; the increase seems to conform to +30%. It also increases damage of all magical attacks, including Elemental Magic. Innin wears off when the player changes areas and can be dispelled. It cannot be used with Ninja as a support job.
This job ability was added in a 2009 version update. As players' levels get higher, jobs like Dragoon and Samurai begin to generate much greater enmity, impairing a Ninja's ability to tank. Innin is a spell to accommodate the fact that at higher levels, Ninja may be more often used for damage dealing. The Ninja must be behind the enemy for most of the effects of Innin to activate. The enmity reduction helps prevent the enemy from turning to face the ninja. It increases the user's critical hit rate, aiding the Ninja's ability to deal more damage. It also enhances accuracy to help the Ninja land attacks from behind, and increases magic damage done by the Ninja when fighting from behind. The downside is that it impairs evasion, making it harder for the ninja to avoid damage.
Innin loosely translates as "Camouflaged Ninja".