It appears that his reaction was fixed per the oracle. But was his battle action changed to once per turn, should it be repeatable, and is that an error on the oracle?
Legacy Osoreru no Oni EXP
A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
It appears that his reaction was fixed per the oracle. But was his battle action changed to once per turn, should it be repeatable, and is that an error on the oracle?
Fear actions with strengths used to be Once Per Battle by the Rules. Now that the Rules for Fear are back in Ivory and changed, we've allowed the current Fear Rules to over-ride the old, so there is no alteration needed to the Oni's battle ability.
On: Osoreru no Oni