Boss: Mergos Wet Nurse
Mergo's Wet Nurse is a multi-blade boss that can easily kill you in one good shot, but she isn't as difficult to fight as you'd think. In fact, this fight will be a close engagement, with you sticking close to her as you circle behind her and wait for the right time to strike.
Start by rushing behind Mergo's Wet Nurse, which will often result in her side-stepping away or circling around to attack, but if you keep moving until she uses an attack you can lay into her with a short combo.
The best times to attack are during her Downward Slash, in which she strikes the ground with all her arms, or the Blender Combo, in which she will attack with all her arms and slowly walk forward. When dealing with the Blender Combo you will in fact be hit, but the minor damage can be easily recovered through damage.
While rushing behind Mergo's Wet Nurse you'll want to watch out for her Uppercut Slash, which will likely one shot you if it makes contact, so back up when you see her preparing this attack by placing all blades on the left side of her body. While it is possible for her to summon the Nightmare Veil, a purple fog that covers the arena, she will likely not get to this point before reaching Phase 2.
List of Mergo's Wet Nurse's attacks in Phase 1:
- Uppercut Slash: Gathers all blades and spins from her left to right for massive damage
- Downward Slash: Smash all blades into the ground after a long wind-up
- Blender Combo: Slashes all blades as she slowly walks forward
- Flying Slash: Lunges forward in a straight line, closing her blades in around you
- Cross Combo: Slashes her blades in three stikes after a long delay for moderate damage
- Nightmare Veil: Covers the arena with a purple fog, reducing visilibity and unlocking additional attacks
- Nightmare Blades: Stretches her arms to stab you during the Nightmare Veil
When Mergo's Wet Nurse reaches below 70% she will enter Phase 2, though the only real difference is that when she summons the Nightmare Veil she will spawn a doppelganger.
The doppelganger has all the same attacks as the nurse herself and will usually teleport to try and get behind you. You should focus on trying to kill the doppelganger, who will die in one hit, or avoiding any fighting during this period.
List of Mergo's Wet Nurse's attacks in Phase 2:
- Deathly Duo: Summons a doppelganger into the Nightmare Veil, who teleports directly toward your left
Drops: 72,000 Blood Echoes and the One Third of Umbilical Cord
Mergo's Wet Nurse
Defeat Great One: Mergo's Wet Nurse.