Brain of Mensis

brain of mensis
Enemy Type Not Beast nor Kin
Health 9837
Drops Living String, 2181 Blood Echoes
Weak ??
Strong ??
Location Nightmare of Mensis

Brain of Mensis is an enemy in Bloodborne.

The Brain of Mensis, also known as "Mother Brain", is an enemy resembling a giant brain with various eyes and some beastly limbs. It is essentially a large version of Winter Lanterns, though without a body.

It is first encountered from a distant tower at the beginning of Nightmare of Mensis,  and will glow orange when the player is in line of sight, causing rapid Frenzy buildup. This attack can hurt the player even from a very long distance, unless the environment is used to avoid its malignant gaze.

The Brain of Mensis  can be slain after defeating Micolash, Host of the Nightmare.  The player can defeat it by using a lever in a side area, dropping the brain into a pit where it will be unable to attack the player further.



  • Have 10 Sedatives equipped. Awaken at the Mergo's Loft Middle lantern, and get into the bird cage elevator. During descent, there is a window you can jump into from the elevator.
  • Run across the bridge with the 3 Winter Lanterns, using the terrain and Sedatives to avoid Frenzy.
  • In the building, run past the Nightmare Apostles, descend the stairs, and pull the lever on the balcony, triggering a cut-scene that drops the Brain of Mensis  into a pit.
  • After the cut-scene, turn around and drop down into a hole on your right.
  • In the room, there are two spiders and a chest holding the Choir Bell item which is guarded by a Winter Lantern.
  • Run outside, jump down into the collapsed tower (avoiding the bottomless pit) and there is a body holding the Blood Rock.
  • Follow the path out onto the bridge and enter the building with Mergo's Attendants.
  • Go to the bottom floor with the holes in the ground, and ride the bird cage elevator located on the right side.
  • You will enter a pitch-black room where the Brain of Mensis  is now helpless and easy to kill.
  • IMPORTANT NOTE: Before attacking the brain, use the "Make Contact" gesture in front of it until your character's arms rotate, and you will receive the Tier 3 Moon Caryll Rune.



Attack Name Attack Description
Gaze If the player is within its line of sight, he/she will take continuous damage from this far-reaching attack.


The Brain of Mensis Information

This enemy is unique as an important part of the story, and it is only found in one area in the game. There are no variants nor is it encountered in Chalice Dungeons.



blood echoes
living string moon
Nightmare of Mensis 9387 2181 (1x) 100% (1x) 100%


Notes & Trivia

  • The Living String description states the Brain of Mensis is a Great One and was found in the Nightmare by Mensis.
  • The location where the Brain of Mensis is dropped after you pull a lever in Nightmare of Mensis is completely pitch black on all of its surfaces, resembling the Abyss of Dark Souls.
  • It will not disappear from the game after you kill it, it will respawn and be able to drop blood echoes but no Living Strings.
  • You can also do the "Make Contact" gesture after killing it (it doesn't have to be physically present) and still get the rune.
  • There seems to be a bug where killing it with a cooperator can cause you to not receive the Living String. The bug seems to be caused by the cooperator landing the final attack, reloading the area and killing the Mother Brain again will get you the Living String.


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    • Anonymous

      please tell me a single place where mensis is called mother brain anywhere official, and not just some guy's funny name for mensis, and decided to edit pages

      • Anonymous

        "The beasts will dangle nectar, and lure the meek into the depths."

        This line from Amelia's prayer always stuck out to me, but now that I think about it, doesn't it kind of sound like a condemnation of Mensis? It appears the Healing Church and the School of Mensis had some kind of falling out some time before our arrival in Yharnam, so I wonder if the Brain symbolizes this "nectar," as if the Healing Church regards it as a false faith used by Mensis to draw the Yharnamites away from the path of righteousness? I assume for the purpose of keeping the masses stupid, and therefore controllable.

        • Anonymous

          this is kne of those feelings where revenge has never felt so good before... Wondrous execution.... Oh, I can't wait... hee hee

          • Anonymous

            This is one of those moments where I'm not sure if I feel bad for it being alive or for relentlessly attacking/killing it for some string, well the pray gesture doesn't do anything here, that's for sure.

            • Anonymous

              Can confirm that she does respawn. I was specifically looking for the Moon rune and when I encountered her I didn't realise she was the brain and killed her. Warped out and returned and she was back, and I was able to get the rune then.

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