The Demon of Obsession is one of three secret bosses in Nioh 3 and arguably the hardest optional encounter in the Bakumatsu era. It waits at the Abandoned Temple Outskirts on the western side of the Nijo Castle area, and reaching it requires following a specific path tied to Kunimatsu's storyline. Defeating it rewards you with a unique Soul Core, a Transformed Art for the Ninja Sword, and the Kunimatsu's Obsession achievement.
Quick answer: Start from the Horikawa Market Shrine, clear the Lesser Crucible to access Mibu Castle, find Kunimatsu's shadow by the stairs across the bamboo thicket, and follow the shadow until you arrive at the Abandoned Temple Outskirts — the boss arena.
Reaching the Abandoned Temple Outskirts
The Demon of Obsession does not appear on the critical path. You need to go out of your way during the Bakumatsu-period missions in the Nijo Castle zone to trigger the encounter. On the map, the arena sits in the top-left corner of the Nijo Castle area.
Step 1: Travel to the Horikawa Market Shrine. This is your starting checkpoint and the closest shrine to the boss route.
Step 2: Clear the Lesser Crucible. Completing this challenge unlocks access to Mibu Castle, which sits between the shrine and the temple outskirts.
Step 3: Look for Kunimatsu's shadow near the stairs across the bamboo thicket. The shadow is easy to miss if you rush through, so slow down once you pass through the thicket.
Step 4: Follow the shadow. It leads directly to the Abandoned Temple Outskirts, where the Demon of Obsession spawns. A cutscene plays before the fight begins.
Demon of Obsession Weaknesses and Resistances
The boss is vulnerable to the Saturated status effect, which you inflict by dealing enough Water element damage. Once Saturated takes hold, the Demon takes significantly more damage from all sources. On the flip side, it resists Electrified, Blustered, and Poisoned — so Lightning, Wind-element offense, and Poison builds are largely wasted here.
| Category | Detail |
|---|---|
| Weakness | Saturated (Water) |
| Resistances | Electrified, Blustered, Poisoned |
| Era | Bakumatsu |
| Recommended level | 130+ |
Combat Strategy for the Demon of Obsession
Being level 130 or higher is strongly recommended. The Demon of Obsession has a much steeper difficulty spike than other encounters available at the same point in the game, so arriving underleveled turns the fight into a war of attrition you're unlikely to win.
Both Samurai and Ninja styles work well, but for different reasons. Samurai style benefits from the boss's slow, heavily telegraphed swings — blocking and deflecting most attacks is straightforward. Watch for the unblockable grab attack and the poison puddles it drops on the ground, which steadily drain your health if you stand in them. Ninja style takes advantage of the fact that the Demon primarily attacks in a forward cone, leaving its back exposed for increased backstab damage. Two moves break this pattern: a spinning advance and a fist slam that triggers an area-of-effect explosion. Stay mobile, and you can punish the recovery frames after either one.
Water element attacks are the centerpiece of any effective loadout. Weapons imbued with Water, the Uncanny Bubble Ninjutsu, Water Familiar and Water Shot Talismans, and the Summoning Seal from the Demon of Pride's Soul Core all contribute toward inflicting Saturated.
Dealing with Poison Puddles and Wind Damage
The Demon periodically creates poison puddles across the arena floor. Circle around them or jump over them rather than trying to tank the damage. If you do get poisoned, use an Antidote immediately — the tick damage adds up fast during a long fight. Equipping gear with Wind Resistance also helps, since several of the boss's attacks carry wind-element properties. Just don't sacrifice too much raw defense for resistance stats; staying alive through big hits matters more than mitigating chip damage.
Using Summoning Seals and Living Artifact
By this stage of the game, you can equip two Summoning Seals at once. Use them aggressively — they deal extra damage, create openings for your own attacks, and can even absorb hits that would otherwise kill you. Save your Living Artifact for the second half of the fight, when the boss becomes noticeably more aggressive. While Living Artifact is active, you're invulnerable, but taking hits still shortens the duration, so continue dodging and blocking. You also gain unlimited Ki during this state, which means you can spam your strongest Martial Arts without worrying about stamina.
Recommended Talismans and Buffs
Power Talismans and Power Pills both boost your attack, though they don't stack with each other — using one while the other is active simply refreshes the duration. Wind Stop Talismans reduce incoming wind damage and pair well with the Wind Resistance gear mentioned earlier.
Several Soul Core talismans give you a meaningful edge in this fight. The Scampuss Summoning Seal (from the Scampuss Soul Core) shreds the boss's Ki quickly. The Life Leech Talisman (Mermaid Soul Core) keeps your health topped up during extended exchanges. The Preservation Talisman (Mujina Soul Core) saves you from a single fatal hit — essentially a free life. And the Barrier Talisman (Otoroshi Soul Core) boosts Ki regeneration while dispelling Yokai Realms the boss may create.
Equipping the Awakening skill is highly recommended for this fight. It speeds up talisman usage, which matters a lot against a boss that can punish long casting animations. Awakening only costs 3 skill points, making it easy to fit into virtually any build.
Demon of Obsession Drops and Rewards
Defeating the Demon of Obsession yields its Soul Core, which has two effects depending on placement in the Onmyo Box. In the Yang Position, it becomes a Summoning Seal that conjures the Demon of Obsession to attack enemies. In the Yin Position, it grants the Hellgust Talisman, which creates a tornado dealing wide-area damage.
The boss also drops the Transformed Art: Kurama Sword Dance Wind for the Ninja Sword — a strong pickup for Ninja Sword builds. And killing it unlocks the Kunimatsu's Obsession achievement, which is tied to the broader trophy list.
Where the Demon of Obsession Fits Among Nioh 3's Bosses
The Demon of Obsession is classified as a secret boss alongside the Demon of Pride and the Demon of Envy. All three are optional and significantly tougher than the main-path encounters in their respective eras. If you've already beaten the Demon of Pride, you can use its Soul Core's Summoning Seal as a Water damage source in this fight — a nice bit of progression synergy between the secret boss encounters. Clearing all three is not required to finish the game, but completionists and trophy hunters will want to track each one down.