Things u need ::

Cheat Engine 5.6 / 5.5 (go to google)
Firefox Browser ~____~

The Steps :

1. open ninjasaga
2. then open process firefox.exe with u’r engine *i use Revolution Engine 8.3*
3. Setting u’r engine with ‘text’ and with checked Unicode
4. select your character then play ► wait till loading complete
5. scan ‘skill41‘ this is Rapid Fist *skill41* and u will get at least 3 address
6. add 3 address that you got in cheat table
7. modify all of the address value to ‘skill91

Note : don’t change your jutsu and your eq,, it might be crash
Note2 : before cheating equip your Rapid Fist then refresh your NinjaSaga

sumber : dengan sedikit tambahan