Balance changed on August 9. Update 1.0.7 lists "various balance adjustments to bosses across all difficulty levels". The official notes don't itemise which bosses changed, so treat the level figures below as launch-week (pre-1.0.7) — weaknesses and rewards are unaffected. See the patch notes tracker.
Quick answer: Kunai and Kirin are a paired Nushi fight, like Shidou & Nue. You fight them twice: Chapter 8 at level 45, then a rematch in Chapter 12 at level 49 — the highest level of any named Nushi in the game. Both fights are weak to Poison.
WeaknessPoison
ChapterChapter 8 and Chapter 12
Boss level45, then 49
TrophyKunai & Kirin (Bronze)

Where you fight it, and at what level

The Chapter 12 rematch at level 49 is the last numbered Nushi you face; only the final boss is listed above it, and that one has no level at all.

EncounterBoss levelSkill reward
Chapter 8Level 45None
Chapter 12Level 49Blade Art: Thunder, Numasugi: Skewer

Both encounters count toward the same trophy — you do not get it until the rematch is done.

Chapter 8 is a scripted loss — you are allowed to lose it

The first fight cannot be failed in the way you think. Game8's reward table literally lists the Chapter 8 encounter's reward as "Scripted Loss", and its fight tips say the story progresses whether you win or lose. If you are pushing for story pace, you can simply let this one go.

The Chapter 12 rematch is not optional — that one has to be won like any other boss.

Fextralife adds a detail Game8 doesn't: taking roughly 20–30% of Kunai's health is what triggers the cutscene in the first encounter. That is a single source, so treat it as a rough figure rather than a threshold to plan around.

Next: everything below assumes a Poison loadout, because that is what both of them are weak to. If you don't have a Poison sword yet, fix that first — the weapons table lists every blade with its element and drop location.

Find a Poison sword

Kunai's moveset

Kunai is a human Purifier and fights like a duellist. Two of her six moves cannot be parried, and — unusually — she can parry you.

AttackWhat happensParry?
Two SlashesA simple two-hit stringYes, both hits
Triple Lightning SlashShe jumps and fires three consecutive lightning slashesYes — or dodge by moving left and right
Greatsword SpinHer sword becomes a greatsword; two full circular swings into a finishing overhead slashYes — but the extended reach means you have to react even at range. Standing back does not make you safe
Blight LungeShe launches up on a pillar of Blight, then dives with a downward strikeNo. She is also invulnerable while on the pillar — don't waste the window attacking her
CounterattackShe parries your attacks and counters
Electric DischargeSword raised, then slammed down into an electric explosionNo. Dodge backwards the moment the wind-up starts

Because she can parry, Game8's advice is to open with Koo's skills to land a status ailment first, then attack while she cannot move — rather than trading melee strings with someone who punishes them.

Kirin Malefact's moveset

Kirin is the beast half and is mostly water- and ground-based. Most of its kit is parryable, which makes it the safer of the two to pressure.

AttackWhat happensParry?
Missile LaunchFlashes a red light, then fires missilesThe missiles only travel a short distance — back away rather than trying to parry
Water BeamStands still and fires a straight-line beamYes — or sidestep
Water SpinStarts like the Water Beam, then spins in a circleYes, twice. This is an open window for Koo
Mud PounceLays mud that slows Emma, then pounces, sprouting roots on landingDon't stand in the mud. The recovery after the pounce is the best punish window in the fight
RushGrows horns at its sides, then charges horn-firstYes — or sidestep as it starts forward
Triple RushThree consecutive rushes with a slight pause between eachYes — the pauses are generous
Rooted CounterattackSprouts roots that counter your melee attacksHit it, then dodge immediately

How to beat them

  1. Fight one at a time. They never telegraph attacks simultaneously, so splitting damage between them just makes the fight longer. Pick one and commit.
  2. Build Koo's Florescence Points on Kunai. Her attacks have clean tells, which makes her the reliable parry target. When the game switches focus to Kirin, stop parrying and start dodging its wide-range attacks instead.
  3. Punish Kirin after the Mud Pounce. That landing recovery is the single clearest damage window either boss gives you.
  4. Respect both counterattacks. Kunai parries and counters; Kirin's roots counter melee. Neither of them is safe to mash on.
  5. Keep ranged options up. Kirin's beam and missiles push you out, so you need something that works from where it puts you.

What to bring

Build for Poison — it is the listed weakness for both halves of the fight.

  • Hunter's Sword (Poison, Envenomed: Poison buildup +8). Fextralife names this weapon for both paired Nushi fights.
  • Poison Arrows and Poison Bolts, stocked up. You will need range against Kirin whether you want it or not.
  • Higanbana: Roots on Koo, to Bind Kunai when she starts parrying everything.
  • For the Chapter 12 rematch specifically, Black Blossom (Poison + Lightning, Poison Storm, buildup +20) is the strongest Poison option if you already cleared the final Shidou & Nue fight, which is where it drops.

At level 45 and 49 these are late fights. If you are arriving under-levelled, Amber farming and a respec are the two fastest corrections. The Koo command list and the combat page cover the mechanics.

Rewards

EncounterBoss levelReward
Chapter 8 — Crater Zone45Scripted loss — no reward
Chapter 12 — The Capital49Blade Art: Thunder · Numasugi: Skewer

Fextralife adds that Kunai's own weapon, Camellia, can be collected from the Cleanse Walker after the Chapter 12 fight. Note that our weapons table lists Camellia as a Lightning blade, not Poison — one third-party guide describes it as a Poison weapon, which appears to be a mix-up with Black Blossom. We are going with Lightning.

Both encounters count toward the same trophy — you do not get Kunai & Kirin (Bronze) until the rematch is done.

What we haven't verified

Correction, August 13: this page previously said "we do not have a move-by-move breakdown for this fight, and we are not going to invent one." That is now out of date — Game8 published full attack tables for both bosses, which we read directly rather than through a search snippet. The tables above are theirs.

Still open: no resistance percentages exist for any boss in this game, from any source, so Poison is a qualitative weakness. No recommended player level is published anywhere — 45 and 49 are the boss levels, not advice. Arena hazards beyond Kirin's mud are undocumented. And Fextralife's 20–30% cutscene trigger is a single source.

Sources

  • Game8 — "How to Beat Kunai and Kirin" (both attack tables, parry verdicts, the "1st Fight is a Scripted Loss" section, the four fight tips and the reward table; page last updated August 11, 2026; read directly in-browser on August 13, 2026, not via a search summary)
  • Game8 — "List of All Bosses" (weakness, chapter and boss level cross-check; read August 10, 2026, re-checked August 13, 2026)
  • Fextralife — Kunai and Kirin (Crater Zone and The Capital locations, Hunter's Sword and Higanbana: Roots loadout, the 20–30% cutscene trigger, Camellia from the Cleanse Walker; checked August 13, 2026)
  • OSLink — boss location guide (encounter locations; checked August 13, 2026)
  • PowerPyx trophy guide (the Kunai & Kirin trophy and its tier, confirming this is a required story fight; checked August 10, 2026)

We do not own the game and do not run first-hand benchmarks or playtests. Every figure on this page is attributed to a named third-party source, and anything we could not verify is marked as unverified rather than filled in.