Okay, aside from having a positively disgusting name, Mergo’s Wet Nurse is actually a super awesome boss. Not only does she grant you one of the three items necessary to achieve Bloodborne‘s true ending, but her constantly-shifting battle techniques make for a fight that keeps players on their toes. This is surely going to wind up being one of the most memorable fights when we look back at From Software’s angry action-RPG, as no two moments truly feel completely the same. More so than any other battle up to this point, you’re going to want to make sure you have as many items in stock as possible. Blood Vials, Quicksilver Bullets, Fire Paper, Bolt Paper, Oil Urns, Molotov Cocktails, Poison Knives (at least five), and the Old Hunter Bone are all extremely useful here, as Mergo’s Wet Nurse boasts a deadly combination of power and speed. Oh, and it absolutely goes without saying (though I’ll continue to say it anyways) that you should grind as much as possible in the Nightmare of Mensis, especially when you consider the sheer number of high-reward enemies wandering around. Of course, you’re nearing the end of the standard campaign, so you probably know this by now.
After you reach the top of Mergo’s Loft, which is easily accessed through the ridiculous number of shortcut-creating elevators floating around, you’ll be treated to the horrifying sound of a baby crying. Simply walk up to the carriage in the center of the arena and Mergo’s Wet Nurse will emerge in one of Bloodborne‘s most disturbing cutscenes to date. This battle changes constantly, though the number of changes and attacks is quite low, all things considered. There are two distinct forms to this fight, both of which can cause reckless Hunters a swift and untimely death. The first part of this battle sees Mergo’s Wet Nurse attack the player in a way that seems quite standard for Bloodborne‘s bosses; she’ll swipe her blade-adorned limbs in a semicircular manner if you’re in front of her, though things start to change when you begin to dash around her sides. Whenever you see the boss begin to swipe in a flurry, make sure to avoid her at all costs. Yes, you can totally get some damage in at this time, considering she moves extremely slowly, but this is one of the few boss attacks that can actually harm players located behind the enemy. Still, considering that the best way to do damage is to use Fire Paper and attack her back, this technique can certainly be worth the risk.
Once Mergo’s Wet Nurse’s health hits the 50% threshold, she’ll cast a purple fog over the arena, making it downright impossible to see more than a couple feet in front of you. To make matters worse, she’ll create a clone that will constantly appear and swipe at you, all while the boss herself warps around the arena at a breakneak pace. While it’s entirely possible to do some real damage during this portion of the fight, you’re going to want to be as evasive as possible here. The worst case scenario comes whenever the clone, or the Wet Nurse herself, spawns directly behind you, as it’s possible to get stuck in a series of attacks. Having the Old Hunter Bone in one of your Quick Equip slots will prove to be extraordinarily vulnerable, as it will allow you to dash around the purple fog without getting hit.
Eventually, due to a combination of occasional melee attacks and time, the purple fog will clear, which gives you the opportunity to do some real damage. Make sure that you try and use your Quicksilver Bullets to stun Mergo’s Wet Nurse whenever possible, as a Visceral Attack will make victory much more achievable. The fog may or may not appear a second or third time, depending on the pace of your offense, so go back into defense mode whenever this occurs. Basically, you’re going to want to get your shots in whenever possible, though this is much easier without any visual obstructions or clones present. After taking your time, playing conservatively, and slashing away at her sides and back (preferably using Fire Paper), the fight should end, and you’ll be able to move on.