Boss souls are unique souls based on their associated Demon Encounter bosses.
How to Obtain
They can be obtained by participating in or discovering Demon Encounter bosses, by exchanging 50 Demon Souls for them in the Mystic Trader shop or by purchasing them from the Soul Shop.
Usage
Boss souls have 2-set effects and grant bonuses to random base stats (excluding Crit DMG and SPD). The 2-set effects provides a passive that only work against monsters (non-player owned shikigami).
Thus, 4-set effects can be obtained from regular soul sets, and multiple of different boss sets can be used together as well.
If equipped on Ushi no Toki, it will trigger if her doll is hit.
Soul Effects
Control Effect
Freeze, Sleep, Confuse, Taunt, Silence, Bind, Morph, Daze, Provocation, Deep Freeze, Frostbound, Shadowbound, Fettered, Ruined, and Rest in Ice are considered to be control effects. The final 9 cannot be dispelled. Frostbound cannot be dispelled or removed.
BanishThis effect is unique to the shikigami Ootakemaru.
Unable to take actions, cannot be targeted, place on move bar cannot be changed, shikigami's passive and souls lose effect, immune to damage, cannot receive healing effects, cannot receive buffs or debuffs.