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 July 2009
Here is the scenario.
I have 3 provinces A, B and C. My opponent attack provinces A and C. I defend at provinces A and C. He decided to resolve province B first. I have no presence and no reason (yet) to create any so I pass. He plays Know Your Center to move someone from province A to province C. He says that this is clearly the way it was intended to be used. I say that because he has no presence at province B and is not trying to create presence at province B he cant play that card at province B. This seems like a no brainer but he is absolutely certain that he can do this.
In case it matters.
Know Your Center Battle: Target your unbowed Personality with 3 or higher Chi: Destroy a target Terrain. Battle: Move your target unit at a battlefield to a battlefield where there are enemy units.
RULE OF PRESENCE To legally take any Battle action, you must control one or more units at the current battlefield. RULES OF LOCATION • To legally take a Battle action from a card in a unit, the unit must be at the current battlefield. • To be legally targeted by a Battle Action, any cards in a unit must be at the current battlefield. Exception: Battle actions that say they move a unit to the current battlefield are legal to take, regardless of Presence and Location, if the rules of Presence and Location would be satisfied with the unit there.
Who is right?
Dan Jacobson (rules official), 1 July 2009
Here is the scenario.
I have 3 provinces A, B and C. My opponent attack provinces A and C. I defend at provinces A and C. He decided to resolve province B first. I have no presence and no reason (yet) to create any so I pass. He plays Know Your Center to move someone from province A to province C. He says that this is clearly the way it was intended to be used. I say that because he has no presence at province B and is not trying to create presence at province B he cant play that card at province B. This seems like a no brainer but he is absolutely certain that he can do this.
In case it matters.
Know Your Center Battle: Target your unbowed Personality with 3 or higher Chi: Destroy a target Terrain. Battle: Move your target unit at a battlefield to a battlefield where there are enemy units.
RULE OF PRESENCE To legally take any Battle action, you must control one or more units at the current battlefield. RULES OF LOCATION • To legally take a Battle action from a card in a unit, the unit must be at the current battlefield. • To be legally targeted by a Battle Action, any cards in a unit must be at the current battlefield. Exception: Battle actions that say they move a unit to the current battlefield are legal to take, regardless of Presence and Location, if the rules of Presence and Location would be satisfied with the unit there.
Who is right?
You are.
Since he is resolving B, the rules of presence and location demand him to either:
Target someone AT B, or Move someone INTO B.
He cannot move someone from A to C while resolving B.
He fulfills both Presence and Location to use Know the Center at B while he is resolving B, to move his unit at B to battlefield C.
Conversely, if your friend resolved C first, and you defended at C and he had no units there, he could still use Know Your Center to move his unit at B into C, because it fulfills the exception to the Rule of Location.