The next two are much harder to get through. Wait on the left until the closer of the two moves to the right side of the bridge. Immediately make a mad dash for the building ahead. You will get hit and you will be frenzied, but heal through it or use a Sedative and make it into the next room. Stay out of the doorway to avoid continued attacks.
There are four spiders in the room here (with human faces). Throw Pebbles to pick them off one at a time if you're worried about fighting them all at once. Continue through the doorway in the far corner and follow the path into the next room. Watch the hole on the right side of the room and head out the doorway at the other end to find a lever. Pull the lever to lower the Brain, then head back into the previous room and drop down the hole.
Head back to the Mergo's Loft: Middle lamp and across the bridge so you can get back down to where you fought Micolash, Host of the Nightmare. Continue down the stairs to the left, go down another flight of stairs, then straight ahead (out of the mist) and down the circular stairs. When you reach a junction, you can continue down the circular stairs to face multiple Tiny Gents and a Lady Gent, and acquire a Moon rune and three Sedatives, but your goal is to the left.
When you reach the mist again, continue straight ahead down two flights of stairs, then turn right. Keep a close eye on the wall to the left, as there's a passage that can be difficult to see. Head down the passage to find a gate at the end, which you have the Iron Door Key for.
Follow the path around to find twos corpse holding a Madman's Knowledge and a Damp Bloodtinge Gem (5). Continue up the stairs to find more corpses holding four Great One's Wisdom items and an Arcane Damp Blood Gem (5). This is normally where a large brain resides to the left that will constantly inflict you with frenzy, but pulling the lever before took care of that. You can drop down into that area to find a Blood Rock, then head through the opening and drop down to the bridge to get back into the castle.
Continue up the stairs directly ahead to find a large room separated by narrow beams in the middle. To the far left are two spiders, but across the room is a Brain Trust and a chest. The chest holds a Choir Bell, which is one of the few healing spells in the game.
Head back to the Mergo's Loft: Base lamp and head inside the castle. Take the lift up to the next level and head down the stairs to the area where you saw the first Lady Gent (where there were large holes in the floor). In the middle of the area there's now a lift. Get inside and drop down to the bottom. It won't look like there's a floor, but there is. Go straight to find the giant Brain. It won't fight back at all, but when you kill it you will obtain the Living String (Holy Chalice ritual).
Once you've defeated Mergo's Wet Nurse, speak to the Doll and she'll tell you that Gehrman is waiting for you at the foot of the great tree. Head to the other side of Hunter's Dream to find that the gate is finally open. Just beyond you'll encounter Gehrman. You can choose to submit your life or refuse. If you wish to fight, refuse Gehrman's offer.
Gehrman fights with a scythe that inflicts solid damage. There are numerous ways you can approach the fight, but it's going to depend on which weapon you're using. If you have a moderately fast weapon you should take the initiative and move toward Gehrman.
As you approach him, Gehrman will try to attack you. Dodge the attack and quickly counter with an attack of your own. You should be able to hit him two or three times in this situation before he dodges away. If you can get his back to a wall you can unleash a barrage of attacks until your stamina runs out (although save enough stamina to dodge away afterward). Most of Gehrman's attacks are two or three hit combos. You're better off dodging toward Gehrman so you are close enough to attack him after the last hit of his combo.
Anytime Gehrman attacks, watch his animations. He has deceptive range, so be ready to dodge away when he flinches. If you see Gehrman place his scythe behind his back, wait a moment and fire a shot at him. The attack that follows can be stunned by your gun, but if you fire too soon you won't get a full stun that leads into a visceral attack. If you fire too late, Gehrman will simply hit you or complete his attack. Keep in mind you need to be close enough to run up and land a visceral attack after the gun shot.
Once Gehrman's health hits 50 percent he will use a Beast Blood Pellet. This increases his attack power and allows him to teleport. He will also jump high into the air and use an attack so powerful that the gusts of wind from the attack damage you. When this happens, continuously dodge until Gehrman is back on the ground. Pay close attention to your surroundings. You do not want to get caught with your back to the wall.
The most important things to remember when fighting Gehrman are to respect his attack range and stay on the offensive. If you allow him to dictate the pace of the fight it will be an uphill battle. Don't wait for him to get close enough to attack. Move toward Gehrman in preparation to attack, then dodge his inevitable attack and hit him with an attack of your own. If you can do this and stun him every time he places his scythe on his shoulder, you shouldn't have too many problems with this battle.
Defeat Gehrman to earn the Old Hunter Badge and complete the game (starting a New Game+). Congratulations! Now stay tuned to discover how to unlock the true ending and defeat the real final boss!
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