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.
I have 3 shadowlands personalities in play. One of them has the Tale of Tsukuro ability. I declare an attack. I didn't assign anybody. Resolved the battle in an undefended province. Can I move either/both of the 2 shadowlands personalities that doesn't have the Tale of Tsukuro ability and have the shadowlands personality with the Tale of Tsukuro ability just stay home...
OR
do I have to move the shadowlands personality with the Tale of Tsukuro ability into the battle as well?
I have 3 shadowlands personalities in play. One of them has the Tale of Tsukuro ability. I declare an attack. I didn't assign anybody. Resolved the battle in an undefended province. Can I move either/both of the 2 shadowlands personalities that doesn't have the Tale of Tsukuro ability and have the shadowlands personality with the Tale of Tsukuro ability just stay home(?)
No.
http://rules.l5r.com/Battles#Combat_Segment: "If a Battle action is on a card in a unit (a Personality or attachment in play), the unit must be at the current battlefield in order to take that action." The ability is on the Personality.
"EXCEPTION: A Battle Action can target or be taken by a card in a unit at another location if its costs or effects say they can move the unit to the current battlefield. Choices within the action must then be taken, if possible, such that they do move the unit there." So it can be initiated at home, but the Personality can't stay there.