Kos Parasite


Imprints (Normal)

radial.png waning.png radial.png

Imprints (Uncanny)


Imprints (Lost)

physical_atk.jpg blood_atk.jpg arcane_atk.jpg fire_atk.jpg bolt_atk.jpg
-- -- 30 -- --
slow_poison.jpg rapid_poison.jpg VS_kin.jpg VS_beasts.jpg durability.jpg
-- -- 100 100 600
Requirements & Scaling
strength.jpg skill.jpg bloodtingue.jpg arcane.jpg qs_bullet_use.jpg
-- -- -- 20

Kos Parasite is a trick weapon in Bloodborne. It was added with The Old Hunters DLC. There are 3 versions of this weapon: Normal, Uncanny and Lost. The only known differences being the Gem Imprints and the locations in which they are found.


Kos Parasite Description

"When the carcass of Kos washed up on the coast, its insides were teeming with tiny parasites, unlike any found in humans.
This atypical weapon can only be clasped tight and swung, but a Kos Parasite is said to stimulate phantasms inhabiting a lumenwood"


Kos Parasite Information

  • Transforms from right-hand tentacle to dual-wield tentacles.
  • Requires 16 Blood Stone Shards, 16 Twin Blood Shards, 16 Chunks and 1 Blood Rock 3,720 Blood Echoes to fully upgrade.
  • You must equip the Milkweed Rune to use this weapon effectively, granting a wider moveset, greatly extended range and an appreciable damage multiplier, far more than is displayed on the weapon. This will transform the player fully into a Lumenwood.
  • To perform a Leap Attack, tap forward on the Left Stick as you press R2
  • To perform a Transformation Attack, press L1 while performing another attack.
  • Whilst the weapon and the Rune are equipped, the player's dash and rolling animations change to become faster and lighter.
  • Without the Rune, the character will have the regular unarmed moveset when using this weapon, however the Arcane damage will be added, meaning it can still be effectively used with good enough gems.
  • For unarmed moveset, only right hand has enhanced unarmed damage,




Uncanny Kos Parasite

  • Purchased at Bath Messenger in any Depth 5 Non-Root Chalice Dungeon (level 3) for 60000 Blood Echoes. (Also confirmed on NG+)
  • If you have the normal version: Create Glyph 8i29rqz3 (Pthumeru Labyrinth) and buy from Bath Messengers up a ladder from the main room for 60,000 Blood Echoes.

Lost Kos Parasite

  • Purchased at Bath Messenger in any Depth 5 Non-Root Chalice Dungeon (level 3) for 60000 Blood Echoes. (Also confirmed on NG+)
  • If you have the normal version: Create Glyph 8i29rqz3 (Pthumeru Labyrinth) and buy from Bath Messengers up a ladder from the main room for 60,000 Blood Echoes.


Player Notes

  • Its trickmode L2 casts a multi-hitting arcane attack for 2 quicksilver bullets, very similar to a smaller Call from Beyond.
  • Backdash R1 in both modes spits a short range projectile forwards from the mouth that causes slow poison build-up.
  • Jumping attack in transformed mode attacks with your tongue/tentacle.
  • Transform attack back to normal mode fires a short range mass of parasites forward.
  • This weapon will not cause you to recoil backwards after you hit a wall. Coupling this with it's great reach, the Kos Parasite is great for attacking through walls or around obstacles.
  • This weapon has a high amount of stagger with every hit, equal to the Beast Cutter. Since the weapon is slow, it makes up for it with making every human-sized enemy or those slightly larger prone to flinching with every hit (regardless of the type of attack). It's ideal as a bait-and-punish tactic weapon and/or "hit & run".
  • Be wary of this weapon's weaknesses, of which there are many. Neutral light attacks are altogether cumbersome to get a handle over, being slow with a mediocre, narrow range and large, easily punished recovery periods between them.





- - 30 - - - - 100 100 - - - A 2


- - 33 - - - - 100 100 - - - A 2


- - 36 - - - - 100 100 - - - S 2


- - 39 - - - - 100 100 - - - S 2


- - 42 - - - - 100 100 - - - S 2


- - 45 - - - - 100 100 - - - S 2


- - 48 - - - - 100 100 - - - S 2


- - 51 - - - - 100 100 - - - S 2


- - 54 - - - - 100 100 - - - S 2


- - 57 - - - - 100 100 - - - S 2


- - 60 - - - - 100 100 - - - S 2


Movesets & Videos


Regular Moveset
Move Damage Type & Modifier Stamina Effect
R1 Combo 1.00x, 1.05x, 1.10x 24 Awkward horizontal and slightly diagonal tentacle strikes.
Backstep R1 .75x 28 Regurgitates pale fluid from the head. Causes poison build up.
Dodge R1 1.29x 28 Sweep and thrusting tentacle strike.
Dash R1 1.05x 30 (+run) Thrusts the tentacle forward.
R2 Attack 1.18x 40 Sweeping horizontal swipe, slight uppercut.
Charged R2 1.35x+103 50 Horizontal swipe.
Backstep R2 1.10x210 42 Performs a backhand diagonal slash from the left shoulder to the right foot.
Dash R2 1.18x 45 Performs a forward thrust with a slight sweep.
Leap 1.23x 50 Leaping head butt.
Transform Attack 1.10x 25 (+x) Wide, sweeping attack from both sides.
Transformed Moveset
Move Damage Type & Modifier Stamina Effect
R1 Combo 1.05x, 1.05x, 1.18x 28 Initiates a left tentacle swipe, right tentacle swipe and then a two handed reach out.
Backstep R1 .75x2 28 Regurgitates pale fluid from the head. Causes poison build up.
Dodge R1 .975x 32 After the roll, initiates a dual tentacle forward strike.
Dash R1 1.10x 35 (+run) Dual tentacle forward strike.
R2 Attack 1.25x, 1.45x 55, ?? A dual tentacle thrust forward.
Backstep R2 1.20x 55 Powerful dual tentacle forward thrust.
Dash R2 1.25x+113 60 (+run) Initiates a dual tentacle forward strike with a longer windup.
L2 (90+113+113+350) 100 Initiates a multi hit arcane attack. Consumes 2 quicksilver bullets. Move is the same for every iteration (backstep, dash, etc)
Leap 1.25x 55 Leaping head butt along with a tentacle/tongue strike from the head piece.
Transform Attack 1.00x 25 (+x) Launch a small burst of parasites forward. Short range projectile, costs no bullets.



  • The Kos Parasite is perhaps the most interestingly unique weapon in Bloodborne in various ways: It is one of two weapons that can reach it's full potential while using a rune (the other being Beast Claw), the weapon itself is not held, it is purely an arcane weapon, it is the only weapon directly dropped by defeating a boss, it has the highest durability of any weapon at 600 respectively, it is the only weapon to have an A-scaling of any weapon without any upgrades and is the only weapon to have an S-scaling by upgrading it twice.
  • It shares other features with the Beast Claw in addition to the Rune synergy, both are tied for the cheapest weapons to fully upgrade at 3,720 Blood Echoes required.





Trick Weapons
Amygdalan Arm  ♦  Beast Claw  ♦  Beast Cutter  ♦  Beasthunter Saif  ♦  Blade of Mercy  ♦  Bloodletter  ♦  Blunderbuss  ♦  Boom Hammer  ♦  Burial Blade  ♦  Cannon  ♦  Chikage  ♦  Church Cannon  ♦  Church Pick  ♦  Evelyn  ♦  Fist of Gratia  ♦  Flamesprayer  ♦  Gatling Gun  ♦  Holy Moonlight Sword  ♦  Hunter's Torch  ♦  Hunter Axe  ♦  Hunter Blunderbuss  ♦  Hunter Pistol  ♦  Kirkhammer  ♦  Loch Shield  ♦  Logarius' Wheel  ♦  Ludwig's Holy Blade  ♦  Ludwig's Rifle  ♦  Piercing Rifle  ♦  PVE Builds and Weapons Review  ♦  Rakuyo  ♦  Reiterpallasch  ♦  Repeating Pistol  ♦  Rifle Spear  ♦  Rosmarinus  ♦  Saw Cleaver  ♦  Saw Spear  ♦  Serrated Weapons  ♦  Simon's Bowblade  ♦  Stake Driver  ♦  Threaded Cane  ♦  Tonitrus  ♦  Uncanny Chikage  ♦  Weapon Moveset Damage Comparison  ♦  Whirligig Saw  ♦  Wooden Shield


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    • Anonymous

      17 Jul 2021 20:31  

      When I have this weapon equipped, my favorite way to greet my fellow hunters that I am cooperating with is to throw up on them, as a sign of friendship.

      • Anonymous

        09 Jun 2021 14:32  

        beating orphan of kos on a pure arcane build was hell but a orgasmic experience finally landing that sweet sweet final swipe

        • Anonymous

          04 Dec 2020 16:43  

          Does the description imply the parasite is just clutched in the hand of the Hunter when not paired with the Milkweed rune?

          • Anonymous

            17 Apr 2020 09:23  

            I feel kinship with any and all broccoli. If I invade you and you're broccoli, I silence blank out. If I co-op with a beckoner and a broccoli invades, I stand aside. If I get attacked by broccoli, I dodge but don't retaliate. "If a broccoli says, I love Kos, and hateth his fellow broccoli, he is a liar: for he that loveth not his broccoli whom he hath seen, how can he love Kos whom he hath not seen? " - Gospel of Broccoli 4:11

            • Anonymous

              13 Oct 2019 00:59  

              Guys, please help me. TL;DR - I went to Isz Chalice Dungeon level 3. Uncanny or Lost Kos Parasite isn't an option I can buy. Where the hell is it??? Long version. I planned out a character build I wanna do, focused around Arcane. I knew this weapon would be wicked for it, and I wanted to get it as early as possible. I made a beeline for Ebrietas so I could get the Isz Chalice. Got through the first two bosses no problem, finally find the Bath Messenger, and bam. Uncanny/Lost variances of Boomhammer, Whirligig, Amygdala Arm, etc. But not the Kos Parasite. What the actual f***?? I also noticed there wasn't a Rakuyo or Ludwig Holy Blade. Now I'm starting to worry that I need to beat Orphan of Kos in order to be able to purchase the weapon. I don't care about PvP. At all. Never have. Never will. If I have to crawl all the way to Orphan of Kos to be able to buy the weapons, at the end of the game, WHAT THE HELL IS THE GODDAMN POINT?!?

              • 19 Jul 2019 11:57  

                The L2 is crazy useful, but the most valuable move on the weapon is the tricked dodge r1. Its range is absolutely insane. I cannot count how many times I've punished someone who thought he was at a safe distance to heal only to get a tentacle surprise from behind finishing them off. I don't think any other weapon in the game has a melee attack with a comparable reach. And it inflicts guaranteed stagger in PvP. Add hunter tools with high ARC to the mix and you have an extremely versatile, powerful build.

                • Anonymous

                  10 Jun 2019 13:47  

                  I literally was at Mergo when I finally got to kos with my Arc/Str build. I got so sick of getting my ass kicked I went to got kill Mergo planning to come back...... and then Gerhman..... and the moon..... and then I realized I forgot something. Don’t forget to kill kos before Gehrman, kiddos

                  • Anonymous

                    24 Feb 2019 03:13  

                    Very underrated weapon. It's basically a heavy version of the whip, slower but with similar range plus poise on its attacks and high stagger. It's a better choice than the Beast Cutter, which is too slow in my opinion (in whip form anyway). The dashing/rolling R1 attack has super long reach and poise, which makes it the best dashing R1 attack in the game. The L2 is insane, dealing very high damage in a large area around you, and it also has poise. You can clear out groups of enemies very quickly with it, and it only costs 2 bullets. Most enemies are staggered by its regular transformed R1s. I would say its only real weakness is lower DPS compared to some other weapons, but if you are stunlocking things or hitting them out of range it doesn't matter. For large enemies who aren't easily staggered, I recommend using the slightly faster 1 handed R1s. Overall it's super satisfying to slap enemies around with it. One of my favorite weapons.

                    • Anonymous

                      23 Dec 2018 15:02  

                      Why would I kill the orphan of kos for this weapon when I could take it from the barrels in the fishing hamlet

                      • Anonymous

                        20 Nov 2018 23:46  

                        When you equip this without the milkweed rune and with best gems it's just litt\urally feels like 'Omae wa mou shindeiru'

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