Sollir,
Well Sollir, as usual my lack of knowledge about Rokugan prevents me from making an accurate judgement. If you wish to try and obtain the 12 scrolls, I could freely assign one to each player and randomly give other ones out by lottery. You would start with one for free, but so would other players.
I do believe the 12 scrolls, if used at once, would have an... interesting affect. If this is an element you want to add to the game, I will allow it.
However, if you want just 1 scroll, and don't want the rest - you can designate it as a 1-time use item that does something rather catastrophic, or a constant affect that generates some Oni for you, or something similar.
If someone else has some more accurate ideas, I'm ready to listen.
Macbrea,
Your sword can grant you, and you only a +3 bonus to all attack and defense rolls. However, in anyone else's hands it only grants a +1 bonus (I'm breaking the rule about it only working for you, so that you will want to protect it more), and can be destroyed by any other PC if they get thier hands on it, by simply stating they do so.