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, 26 October 2007
Sorrow's Path Before a battle at this province resolves: The Attacker targets one unit, or three cards, in the attacking army. Destroy the targets.
Encircled Terrain Terrain Battle: Before this battle’s resolution, the Attacker and Defender, in the order of your choice, each choose one of his units at the current battlefield. Then, move all other units there home.
both of these seem to occur at the same time. If Encircled Terrain is played at a battlefield at a province with Sorrow's path attached, in what order do these effects occur?
Martin Lund (rules official), 2 November 2007
Sorrow's Path Before a battle at this province resolves: The Attacker targets one unit, or three cards, in the attacking army. Destroy the targets.
Encircled Terrain Terrain Battle: Before this battle’s resolution, the Attacker and Defender, in the order of your choice, each choose one of his units at the current battlefield. Then, move all other units there home.
both of these seem to occur at the same time. If Encircled Terrain is played at a battlefield at a province with Sorrow's path attached, in what order do these effects occur?
Delayed Effects waiting for a trigger always get applied before new Trait Triggers for a given Timing Trigger.
As per the Comprehensive Rules - Timing.
Basically, at any given timing trigger you apply effects in the following order:
A.) Ongoing or continuous effects that negate or otherwise modify the occurrence that defines the trigger.
(Kihos this Personality performs are Maho)
B.) Continuous effects
(Has +3F while in an attacking army)
C.) Rulebook Triggered Effects
(rehonoring Personalities instead of Honor gain)
D.) Delayed Effects
E.) Triggered Traits on Cards
F.) Reactions
(A Test of Courage)
Encircled Terrain always works at Step D. Sorrow's Path triggers at Step E.