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.
A player, 9 March 2009
If my opponent's Doji Hakuseki has targetted my Daigotsu Churo (as an example), and I have elected that he cannot use his ability.
My opponent plays Imperial Summons on Daigotsu Churo to bow him. Since the "cannot" clause in Hakuseki's ability is negation, can I use his action via Determination to negate the bowing?
Thank you.
Hakuseki: Limited: Target another player's Personality. His controller may choose to have you gain 3 Honor. If he does not choose this, the Personality can not use his abilities until your next turn begins.
Determination: Dark Virtue Reaction: After you announce an action, target one of your Samurai: The action cannot have its effects negated or have its targeting changed. After the action destroys any Personality, remove him from the game.
Dan Jacobson (rules official), 9 March 2009
If my opponent's Doji Hakuseki has targetted my Daigotsu Churo (as an example), and I have elected that he cannot use his ability.
My opponent plays Imperial Summons on Daigotsu Churo to bow him. Since the "cannot" clause in Hakuseki's ability is negation, can I use his action via Determination to negate the bowing?
Thank you.
Hakuseki: Limited: Target another player's Personality. His controller may choose to have you gain 3 Honor. If he does not choose this, the Personality can not use his abilities until your next turn begins.
Determination: Dark Virtue Reaction: After you announce an action, target one of your Samurai: The action cannot have its effects negated or have its targeting changed. After the action destroys any Personality, remove him from the game.
While "cannot" when referring to costs or effects on cards is indeed negation, Doji Hakuseki's "can not" is a restriction on whether an ability can be used. It is not legal to even announce Daigotsu Churo's ability at that point, much less Determination having any effect.