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, 17 June 2008
"Maho Reaction: After you attach an Item, give Keitaro a -1C Corruption token: Draw a card."
So, giving Keitaro the -1C Corruption token is clearly in the constraints block, and is therefore a cost.
Now, if Keitaro has some effect on him (such as an attached item, etc), that negates chi penalties, when using his reaction, does the penalty negation cause the cost to not be paid in full (for example, Hida Daizu with such an item, trying not to die failing because he cannot fully give himself -2C), or is the cost simple giving him the token, which then causes the chi penalty, which is then negated?
We've been playing it as the -1C "effect" of the token is still part of the cost of his reaction, but it's recently been argued that giving the token is the totality of the cost, even though the chi penalty may be negated. In which case, the cost will always be paid in full (barring some effect preventing him from receiving tokens), regardles of whether or not he can actually receive a chi penalty.
Alex Jones (rules official), 17 June 2008
"Maho Reaction: After you attach an Item, give Keitaro a -1C Corruption token: Draw a card."
So, giving Keitaro the -1C Corruption token is clearly in the constraints block, and is therefore a cost.
Now, if Keitaro has some effect on him (such as an attached item, etc), that negates chi penalties, when using his reaction, does the penalty negation cause the cost to not be paid in full (for example, Hida Daizu with such an item, trying not to die failing because he cannot fully give himself -2C), or is the cost simple giving him the token, which then causes the chi penalty, which is then negated?
We've been playing it as the -1C "effect" of the token is still part of the cost of his reaction, but it's recently been argued that giving the token is the totality of the cost, even though the chi penalty may be negated. In which case, the cost will always be paid in full (barring some effect preventing him from receiving tokens), regardles of whether or not he can actually receive a chi penalty.
The cost is to give Keitaro a token. If that is done, the cost is paid. Whether or not the token has any effect is irrelevant.