Way of the Samurai 3

The ninja dual sword stance is a unique stance for two ninja style blades rather than two normal blades or one ninja blade and one normal sword. Anyway, the best way to learn skills is to purchase the scrolls from a merchant in the posting station. Not only can you buy the scrolls for this stance, you can also purchase scrolls for bare handed , standard dual sword as well as a weapon safe each time you go as well as scrolls to unlock basic, advanced and special skills. Anyway, purchase whatever you wish to purchase (I'm assuming it's Ninja Dual Sword scrolls at least considering you are reading this guide) and exit the menu. After, Kill the merchant and pick up your yen. Leave Amana rinse and repeat. Eventually you will pop your 3 easier stance achievements as well as get a few extra scrolls/a weapon safe or two on the side.