Drop it like it’s hot.
Bloodborne is a difficult game, no doubt about it, but that’s part of its charm. Fortunately it provides you the means to grow stronger and subsequently overcome its many hardships. One way of improving your power is by fortifying your many weapons. This requires materials, and as you increase your weapon’s power the materials that are required will change, and it is always of an increased rarity. Once your weapon reaches +9 you will need a Blood Rock in order to bring it to max level. Unfortunately, there is only one Blood Rock to be found in each story playthrough, and it happens to be guarded by a particularly nasty enemy.
During the fight with Micolash, Host of the Nightmare you had the opportunity to locate an Iron Door Key, if you failed to do so, double back through the second area of that fight and make sure to pick it up. Once you have it in your possession, head back to the entrance to the boss fight, it will now be a room missing a central platform (it moved up after the boss fight). Walk along the side and you will discover the locked iron door which you can now open. If you follow the path you will discover the location of the Blood Rock which is also the same place where Micolash was keeping an extremely large, very deadly brain. This is the Mother Brain, and it is no easy task to defeat. But, if you want that Blood Rock, and you don’t want to die, you’re going to have to get rid of this nasty menace that’s blocking your way.
Luckily, it turns out that you can get rid of this brain without actually fighting it, thus freeing up the path for you to get that highly coveted Blood Rock. Head back to the lantern that activated after defeating Micolash and continue as if you were heading to the next boss. Before you get to the boss you will find an elevator shortcut just like others you may have encountered earlier in Micolash’s Nightmare. You’ll know you’re at the right one because the elevator’s door will be broken. Get into it and as it descends rotate the camera. You will see an open space that you can roll into. Follow this path and there will be a lever, pull it and enjoy watching the Mother Brain crash down into the abyss.
Now just return to the iron door you unlocked, head back to the area where the brain was and look down. You’ll see a dead body with that lovely item glow. Jump down and collect your prize, the super rare Blood Rock is finally in your grasp. You can also obtain one from high level Chalice Dungeons (like Isz Root Chalice), but it is an extremely rare drop and may take a lot of run throughs.
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