If you have the Fourth Legathy Skill chip (beat game once in store for 44444 ryo) then go to the mission Fires of Vengence (S-rank but the easiest one) keep doing it until you have 99 multi kunai or shurikans (can't remember which) but any who go to a mission with bandits and continuosly throw them at the bandit. The big virtue orbs will keep coming out then grab them.
Note:They are worth ten each so use the chip virtue orb bonus which will make them wourth twenty eack

good luck ninja