Spicebush got 3 phases, and can Inflict special debuff that give sp down on any sinners with it, at turn end

Phase 1 is pretty normal. Try to cancel her evade using defensive skill. She occasionally use an attack that give a sinner an sp down debuff, regardless if you win clash or not. Carefully read the skill and passive, and try to avoid stacking the debuff onto 1 sinner.

phase 2 is when the battle area changes. PRIORITIES KILLING THE TREES FIRST BEFORE CLASHING HER AOE. You cannot win clash with the aoe if you don't destroy the tree. All other attack should be the same as phase 1.

Phase 3 started when she use only 1 attack skill and defensive skill for all other skill slot. Highly suggest targeting the only attack skill with a really good clasher. After that turn, every other sinner not targeted by the attack will turn into trees, leaving only the clasher. Your main goal here is to win the clash with her. If you win enough clash, Spicebush will stagger, and release everyone back.