Tonko: Ni is a Ninjutsu spell in Final Fantasy XI. It is an upgraded version of the Tonko: Ichi ninjustu. It is learnable by Ninjas at level 34. When used, the spell will consume one Shinobi-tabi to grant the Invisible status on the caster, preventing enemies from detecting them by sight. It does not prevent enemies with True Sight from seeing the player, nor does it prevent aggro from monsters that detect by sound.