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, 10 July 2010
Utaku Kohana Unicorn Clan • Samurai • Cavalry • Battle Maiden • Paragon • Experienced • Unique After the resolution of an action which gave a Force penalty to any enemy cards at the current battlefield, if Kohana is there: Gain 1 Honor. Battle: Bow Kohana: Bow a target enemy Personality with lower Personal Honor.
Rules question: If a personality whose Force is already 0 is targeted with a card like Desperate Rush, does Utaku Kohana's trait trigger? More specifically, with minimum Force as 0F, is a force penalty considered applied after 0F?
Togashi Azrael
Zen Faulkes (rules official), 10 July 2010
(W)ith minimum Force as 0F, is a force penalty considered applied after 0F?
Penalties still occur even after a card has reached its minimum. See: http://rules.l5r.com/CE_Card_features#Calculating_stats
The Experienced Utaku Kohana's trait will go off if a card with 0F gets a -3F penalty, which is then rounded to 0F.