Oritsuru » Shadow Hearts From the New World » Ninja Village Sidequest
The Ninja Village is a sidequest specially targted towards Frank. In order for the Ninja Village to show up on the world map, you will need to have entered the final dungeon once and also have all of Frank's Ninja Art skills. If you fill these two requirements, head back to Rio and go to the dumpster on the second screen. You'll find Britney standing around. Talk to her and you'll be able open up the location.
The Ninja Village acts just like any other town, with the exception that it's a heck of a lot more vibrant than many of the other areas of the game. You should find several treasure chests around the main area and even Baigen and Mazymell are there. The awesome thing is, that they have most all the items they've sold to your party throughout the course of the game, so be sure to stock up.
When you are ready, go to the left side of the village and head to the bridge. Some scenes will be triggered. Head inside afterwards and talk to the man in there. He'll tell Frank that he wants to give him a test, so you're mission now is to complete that said test!!
If you go up to the upper left side of the screen, you'll be able to head into the Momonga area. You should see a tall structure. Talk to the man at the structure and they'll explain how the whole crazy thing works. You'll even be able to practice a bit before Frank jumps into the real thing. Whenever you are ready, head up it.
This place is rather crazy, and if you just go on the straight path, you'll not actually be able to recieve the hidden writings that Frank needs in order to meet with the head of the village for battle. But, you will probably want to go through it straightforwardly one time though in order to get all the loot from the treasure chests, not to mention, you can level up pretty easily one the ninja's in the area, and they have the tendency to drop lottery tickets, which is a plus.
If you want the secret writings straight away, you'll need to head to the 12th area. In order to do this, you'll have to set it at 185 on the 8th area. It shouldn't be too hard.
You'll now, with the secret writings, be able to access the area that the ninja was blocking. Make sure Frank is properly equipped. He should have the strongest equipment and the shield spell.
When he battles the Ninja Head, you'll want to use shield ASAP and possibly a gale stellar. This can help boost Frank's speed which would be very helpful in the battle. From there, it's really straightforward. Just remember to cancle out his attacks before he is able to double!
For winning, Frank will recieve the Hot Sword, his ultimate weapon in the game! And if you talk to the Ninja Head, he'll give you a stellar.