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Boss guide · Chapters 8 & 12

Kunai & Kirin: The Second Dual Fight

Kunai & Kirin is the roster's second two-body encounter, opening in Chapter 8 and resolving four chapters later in the run-up to the finale. The discipline it asks for is the same one the earlier dual fight teaches, but the timing is harsher: you meet it at Level 45, inside a chapter that already has another apex Malefact in it. Here is what our coverage establishes about both encounters.

Compiled from this site's own launch guides · Last reviewed September 11, 2026

Two encounters, four chapters apart

Our boss list records the pair twice: a first meeting in Chapter 8, the chapter titled Worm Food, with the fight listed at Level 45, and a resolution in Chapter 12 (The Firmament) at Level 49 — the highest level attached to any numbered encounter on the roster.

Both appearances land in crowded chapters, which is worth knowing before you plan a route. Chapter 8 also holds the Taurus rematch at Level 44, one level below this fight. Chapter 12 also holds Erymanth at Level 47, two levels below the resolution here — so the recorded level ordering puts Erymanth first and Kunai & Kirin last before the finale. Our walkthrough groups Chapter 12 into the capital-and-finale stretch, listing Erymanth and the Kunai & Kirin rematch together in the same breath ahead of the Beast of Reincarnation itself.

How a dual fight is played

Two of the eleven story bosses are dual encounters, and our boss list gives them the same prescription. For Kunai & Kirin it says to apply the discipline learned on the first dual fight: fight whichever is active and bank through the swaps. The walkthrough phrases the earlier pair's version as parrying whichever is active and spending Florescence Points in the swap gaps.

That is a resource-timing instruction more than a combat one, and it follows directly from how the economy works on the Koo guide: FP banks into a shared pool and carries between exchanges rather than draining between them. A fight with a scheduled hand-off is therefore a fight with scheduled spending windows. You are not looking for an opening in the middle of pressure; you are waiting for the transition the encounter gives you for free.

The command menu is the other half of it. The Koo guide describes it as slowing time without pausing the fight and recommends opening it whenever you are confused rather than only when you intend to spend — advice that fits an encounter where the thing you most need to know is which body is currently the threat. For a worked example of the same structure earlier in the campaign, see the Shidou & Nue guide.

The Poison weakness

The boss list records Kunai & Kirin as weak to Poison, the same weakness it gives Shidou & Nue and the Nue Malefact. Three of the eleven story bosses share that label, making Poison the most common weakness on the roster.

As with Acid and Explosive, though, Poison is not among the three enchantable elements our weapons page confirms in the shipped build; that page lists Fire, Lightning and Wet, and states that the complete enemy-weakness chart was still being catalogued after launch. So how you deliver poison damage is not confirmed here. What the site does document is a poison ability line: the Lacerta fight in Chapter 2 grants Dokuzeri Shower, Dokuzeri: Fang and Blade Art: Dokuzeri, and the boss list explicitly frames the Dokuzeri kit as built for the Poison-weak fights that follow. If you have kept those arts invested in across ten chapters, this is one of the places they are aimed.

What the resolution unlocks

The first encounter is not where the payout is. The boss list ties both rewards to the Chapter 12 fight: Blade Art: Thunder and Numasugi: Skewer. Our walkthrough agrees, naming Blade Art: Thunder as what the Level 49 resolution unlocks.

Note what is absent: no Nushi Skill. The Koo guide's documented Nushi Skill list ends at Acid Burst Nobudou from Corvus in Chapter 7, with later seals contributing art upgrades and Finishers instead — and Kunai & Kirin fits that late-game shape. Our glossary keeps the two categories separate: a Nushi Skill is absorbed from a sealed region ruler, while a Blade Art is a different class of boss-fight unlock. Getting Blade Art: Thunder at Level 49, one chapter from the end, means it is a reward you will mostly spend in New Game Plus — which our endings guide notes is required for full completion anyway.

Loadout notes

  • Bring the Dokuzeri line if you have it. It is the only poison toolkit this site documents, and the boss list points it at exactly these fights.
  • Arrive with FP banked. The Spirit Stones guide lists Entanglement Stone, which starts combat with Emma's Entanglement Gauge and Koo's FP already raised (+1/+1 up to +3/+3 across three levels) — useful when the first spending window arrives on the encounter's schedule rather than yours.
  • Stones that reward clean defence. Entangled Parry and Entangled Dodge both have a chance to return 0.2 of the Entanglement Gauge and 1 FP, scaling from 10% to 50% over five levels — the two sides of a fight where you will be doing plenty of both.
  • Check your slot count. The same guide says Emma equips up to four Spirit Stones early and up to six by the end of the game; by Chapter 12 you should be near the upper bound.

Completion data

The achievement is simply named Kunai & Kirin — without the possessive "End" construction the single bosses use, which our trophy page also shows for the other dual encounter. It sits at 24.3% of Steam owners on that page's August 31 read and at 25.6% on the achievement tracker's September 7 refresh.

That places it inside the late-game cluster the trophy page describes, where Ursa, Shidou & Nue, Erymanth and this fight all land between 24% and 25% before the final-boss achievement at 24.0%. In plain terms: the handful of players who reach Chapter 12 almost all finish, so the resolution here is far less of a filter than its Level 49 tag suggests.

What this page does not claim

Our coverage does not say which of the two is Kunai and which is Kirin, what either looks like, whether they share a health bar, or what any of their attacks do. The tactical advice above is the roster-level instruction for dual encounters plus the general economy that applies to every large Malefact. We also cannot tell you what the Chapter 8 encounter awards, only that the recorded rewards are attached to the Chapter 12 fight.

Kunai & Kirin FAQ

When do you fight Kunai & Kirin?

Chapter 8 at Level 45, then a resolution in Chapter 12 at Level 49 — the highest level listed for any numbered encounter on the boss list.

Is it the same as Shidou & Nue?

No, but it is the same kind of fight. Both are dual encounters weak to Poison, and the boss list gives them the same core instruction: fight whichever is active and bank Florescence Points through the hand-offs.

What do you get for beating them?

Blade Art: Thunder and Numasugi: Skewer, both tied to the Chapter 12 fight. No Nushi Skill is recorded for either encounter.

How do I do Poison damage?

Not confirmed on this site as an equippable element — the weapons page lists only Fire, Lightning and Wet. The documented poison toolkit is the Dokuzeri art line from Lacerta in Chapter 2.

Sources on this site

Every figure above is drawn from the following pages of this guide, each of which names the outside material it was checked against:

Last reviewed: September 11, 2026 · Game version checked: 1.0.11 · Every figure on this page is sourced from the pages listed above; where they disagree or fall silent, this page says so instead of choosing.