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, 1 September 2014
The card Strength Remains says that the opponent must focus at least once from their hand, and it has been ruled that the opponent may focus from top of their deck first.
Suppose the following situation occurs:
I play strength remains, targeting my 1C courtier, and my opponent;s 3C samurai. My opponent chooses to focus from the top of his deck first, I then strike. Is my opponent required, in that case, to play a focus card from hand? I would suspect not, as the duel is ended and he is no longer "able". If so, does he have to substitute from hand for his top card, or add another from his hand?
Jon Palmer (rules official), 24 September 2014
The card Strength Remains says that the opponent must focus at least once from their hand, and it has been ruled that the opponent may focus from top of their deck first.
Suppose the following situation occurs:
I play strength remains, targeting my 1C courtier, and my opponent;s 3C samurai. My opponent chooses to focus from the top of his deck first, I then strike. Is my opponent required, in that case, to play a focus card from hand? I would suspect not, as the duel is ended and he is no longer "able". If so, does he have to substitute from hand for his top card, or add another from his hand?
He is not required to do anything additional in this case. You have pre-empted the effect of Strength Remains by choosing to strike.