Mergo's Wet Nurse

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Description

Playthrough	HP	Bloodechoes	Kind
First	14,081	72.000	Neutral
NG+
NG+6

Info	Physical Def	Blunt Def	Thrust Def	Blood Res	Arcane Res	Bolt Res	Fire Res	Slow Poi Res	Rapid Poi Res
NG	148	177	148	148	75	75	75	250	180

Item	Notes
Third Umbilical Cord

After you defeat the boss, a Lamp will appear which will allow you to warp back to the Hunter's Dream;
A red-tinted "Nightmare Slain" message will appear after her defeat, instead of the normal green-tinted "Prey Slaughtered". Also, the message doesn't appear right away after she dies, but just when the baby's crying dies out and everything goes silent;
- - - - The apparent delay of the message may happen because the Wet Nurse, though being the stage boss, is not your real target; that would be Mergo, the "nightmare newborn" she takes care of. He is the true source of the nightmare, thus explaining the "Nightmare Slain" message.
Playing the Tiny Music Box before the cries fade out will cause Mergo to laugh one last time;
If you come back to the Pthumerian Queen standing under lunarium after defeating Mergo's Wet Nurse, she'll bow to you as a sign of gratitude.
It is possible that the Wet Nurse is an eldritch version of the Shadows of Yharnam mob that the player encounters throughout the game. They have some similarities, like the apparent invisible faces/heads and the ability of greatly stretch their arms.

Her main attack is to shred the area in front of and around herself with all of her sickles, slicing and dicing for a few seconds.
If you stay behind her for two long, she may slash behind her body.
Occasionally she may shroud the entire arena in a nightmarish fog then proceed to continuously spawn clones of herself to attack you every few seconds until the fog dissipates.
Teleport away a short distance.
Raises blades up and brings them down on the ground in front of her.
Twirls around into a blade uppercut.

Dodging past her and attacking her back is fairly easy, though some of her slices may still hit you. The fight shouldn't take too long.
Weak to Rapid Poison.
Lock on her while shrouded in the fog and stay near as possible; this will limit her attacks to the point she might only do the "slice-and-dice" one, providing a huge opening for consecutive attacks at her back.
Don't let her leave your sight field while in the fog, or she and her clone will start attacking and teleporting at the same time; together they have a respectable range and attack very close to each other, making difficult to find an opening to counterattacks or healing.