Mergo: the Unseen Infant Great One of the Nightmare of Mensis
Mergo is the infant Great One whose cry fills the Nightmare of Mensis, guarded by Mergo's Wet Nurse. You never see it, but killing its nurse ends the night. Here is what Bloodborne says about Mergo and what players think it is.
Mergo is an infant Great One kept at the top of the Nightmare of Mensis, the dream world built by the School of Mensis. You never see it. You hear it crying, and you fight its guardian, Mergo's Wet Nurse, as the last required boss of Bloodborne. (Bloodborne)
What the game says about Mergo#
Almost everything comes from one item. The Third Umbilical Cord dropped by Mergo's Wet Nurse reads: "Every Great One loses its child, and then yearns for a surrogate. This Cord granted Mensis audience with Mergo, but resulted in the stillbirth of their brains." (Bloodborne)
The notes do the rest. After Rom dies at Byrgenwerth's lake and the moon turns red, one appears in Yahar'gul: "Ritual secret broken. Seek the nightmare newborn." Another, by the Hypogean Gaol lamp, says: "Nightmarish rituals crave a newborn. Find one, and silence its harrowing cry." A third, in a cell: "The Mensis ritual must be stopped, lest we all become beasts." (Bloodborne)
The School of Mensis and the nightmare#
Mensis reached for Mergo with the cage. The Mensis Cage says the school "controls the Unseen Village", that the cage restrains the will of the self, and that it works as "an antenna" for contact with "the Great Ones of the dream". The same text adds that to an observer it "appears to be precisely what delivered them to their harrowing nightmare." (Bloodborne)
Micolash hosts that nightmare. He prays to Kos for eyes as you chase him through it, and his last words when he dies are "Now I'm waking up, I'll forget everything..." The Living String says Mensis also pulled a huge rotten brain out of the nightmare, "a legitimate Great One" lined with evil eyes. (Bloodborne)
The Wet Nurse and the end of the night#
Mergo's Wet Nurse waits on the roof of Mergo's Loft. Its trophy reads "Defeat Great One: Mergo's Wet Nurse", so the game counts the nurse itself as a Great One. A baby can be heard crying through the fight. (Bloodborne)
When the nurse falls the crying stops and the screen reads "Nightmare Slain". The hunter gets the third Umbilical Cord. Back in the Hunter's Dream the workshop is burning, and the Doll says: "Dawn will soon break, this night and this dream will end. Gehrman awaits you, at the foot of the great tree." That leads into the endings. (Bloodborne)
Queen Yharnam: the mother question#
A Pthumerian woman in a bloodstained dress stands near the lift to the Wet Nurse's Lunarium, staring upwards. In the Chalice Dungeons she is Yharnam, Pthumerian Queen, the trophy calls her "Blood Queen of the Old Labyrinth", and in that fight an unborn child cries from her belly. The Yharnam Stone says "the Queen lies dead, but her horrific consciousness is only asleep". (Bloodborne)
Put together, most players read Mergo as Yharnam's child, taken or born into the nightmare, with the bloody dress pointing at a lost pregnancy. It's a strong reading, but the game never states it, and the father is anyone's guess. The usual suspect is Oedon, the formless Great One, since another cord ties Oedon to a different birth. (Bloodborne)
What else the game never confirms#
Nobody agrees on the Wet Nurse. Some players think it is Mergo's own projection, since it copies itself in a shadowy space; others take the name at face value. Also unclear is how directly Mergo causes the beasts and the red moon. The notes tie the Mensis ritual to everyone becoming beasts, and the workshop note says escaping the Dream means halting "the source of the spreading scourge of beasts". Reading Mergo as that source fits, but it is a reading. See the Great Ones and Yharnam. (Bloodborne)
Frequently asked questions
- Who is Mergo in Bloodborne?
- An infant Great One at the top of the Nightmare of Mensis. The School of Mensis reached it with a Third Umbilical Cord, and its nurse, Mergo's Wet Nurse, is the last required boss.
- Who is Mergo's mother?
- The game never names her. Most players believe it is Queen Yharnam, the Pthumerian queen who appears in the Nightmare of Mensis in a bloodied dress, but that is an inference.
- Does killing the Wet Nurse kill Mergo?
- The crying stops and the game declares "Nightmare Slain", so most read it that way. The game never shows Mergo itself.
- Why does Mergo matter?
- Notes say Mensis rituals "crave a newborn" and must be stopped "lest we all become beasts". Ending Mergo's nightmare is what lets the night end.
Sources
- GameBloodborne, FromSoftware, 2015
Spotted a factual error or a primary source we missed? Email a correction. Every flagged claim gets reviewed.
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