Set in the 4th year of Tenshou Era during the Warring States Period (around 1567) of Japan, it tells a dramatized version of the Battle of Murayama, between the Oda clan and the Ninja of Iga province.
The story features an ensemble cast of questionable sanity and morality drawn together in a conflict of politics and ideologies: a young ninja disillusioned by his people's way of living, his lazy nemesis secretly struggling to maintain his love-life, and a bunch of sly politicians with hidden agendas.
Tropes used in Shinobi no Kuni:
- Anti-Hero: Everyone, with the women as possible exceptions.
- Beware the Nice Ones: Heibe seems like a meek, kind-hearted young man until he put his Cool Mask on. Carnage will follow.
- Black-and-Gray Morality: No character is depicted as morally correct. Even the most noble samurais are not able to follow their conscience because of their Undying Loyalty.
- Brilliant, but Lazy: Mumon.
- Charles Atlas Superpower: Apparently Iga ninja develop their ability to move at wind's speed and leap to twenty feet above ground because they used to be workers of castle and temple constructions on mountainous forests, which despite obvious difficulty still demand them to move as fast as possible.
- Chronic Backstabbing Disorder: Nearly everyone. However, Saburouzaemon takes the cake.
- Dude Looks Like a Lady: Bungo.
- Evil Old Folks: Iga's council of twelve families.
- Goes Mad from the Revelation: Both Heibe and Saburou slowly goes mad and vengeful once they realized how screwed their society's morals and norms are.
- Gold Digger: Lady Okuni.
- Henpecked Husband: Not yet married actually, but Mumon is really afraid of his lover's wrath.
- Hoist by His Own Petard: Saburouzaemon pays the Iga ninja to help him rebuild Maruyama Castle which he secretly intends to use to invade the region. The Igas later burn the finished castle, demolishing Oda army with it.
- Honor Before Reason: Daizen reveals Saburouzaemon's scheme to Iga's council of twelve families because he doesn't want to wage war against an enemy stupid enough to fall under such simple tactic.
- Large Ham: Oda Nobunaga.
- Obfuscating Stupidity: Sandayuu and co. look like a money-crazed individuals with brains of chimps. But no. They will pretend to fall into your money-filled to trap to turn it against you and extort more money from it.
- Only in It for the Money: A ninja's most common motive for anything he does.
- "Well Done, Son!" Guy: Oda Nobukatsu.
- World of Badass