The Grave of Saints
Head into the mouth-like entrance, take out the two zombies on the way in, then the four rodents of unusual size in the room ahead. The rodents come at you from both directions, so be careful when fighting them and try not to get surrounded. If your level is high enough, they will likely go down in a single hit, but you should still be wary.
Head around to the far side near the open doorway to find a Large Soul of a Nameless Soldier, then head through the doorway and up the stairs.
Four more rodents attack from the right, but take note of the face on the floor near the top of the stairs as you'll need to access it later. Take down the rats, then head to the left and kill the zombie at the end. Pick up the item to obtain three Small Smooth & Silky Stones. Use a Pharros' Lockstone in the previously mentioned face if you have one available. This is the only face that you should interact with; the others will not benefit you, so ignore them.
If you used a Pharros Lockstone, head across the bridge and into the room just beyond. Go to the right side of the room and kill the rats that spawn, then pick up the item to obtain two Poison Moss. Continue up the stairs to find a Whisper of Despair and a Torch. You can't go any further because the way is blocked, so head back across the bridge and to the far left end of the hall. Climb up the ladder on the right to reach the next floor.
Rhoy the Explorer invades when you reach the top of the stairs, in addition to two more rodents, one from either side. Take down the rodents while avoiding Rhoy, then focus on the invader. Continue through the broken wall to the left to find three Homeward Bones, then head down to the other end of the hall to find two more rodents and a bonfire.
Light the bonfire, then prepare to head into the mist down the corridor to the right. Inside the mist you will face a plethora of rodents, followed by the Royal Rat Vanguard.
Boss Battle: Royal Rat Vanguard
In this battle, you must face off against a horde of rats as well as the Royal Rat Vanguard. If the rodents attack too many times, they will petrify you, even if you're guarding. To avoid this, equip gear that increases petrification resistance, such as the Ash Knuckle Ring found in the Gutter. In addition, the Royal Rat Vanguard poisons you with each attack, so poison prevention gear and items should also be used if available.
Luckily, this is one of the easiest boss battles in the game. While normal rats continue to pile into the area, you only need to defend against them for a short time. Kill any rats within your immediate area, as you move around the room to avoid getting ganged up on. After about a minute has passed, the health bar for the Royal Rat Vanguard appears and the fight proper begins.
Once the health bar is visible, look out for your target: it's the same size as all the other rodents, but it has an unusual amount of black fur on its back. As soon as you spot it, lock on and don't change targets.
While this rat has more health than the others, it's not by much. You should be able to take it down by continuously attacking until your stamina bar is depleted. In the worst case scenario, it should only take two stamina bars worth of attacks; back away if you deplete one and you haven't taken it down. If you move to the opposite side of the room, you'll have time to use a health item while the rats catch up. Heal up, then go back in for the kill. Once the Vanguard is down, the remaining rats retreat. Kill them as they flee for additional souls.
With the Vanguard down, head through the doorway at the end of the room that was previously blocked by mist. Speak with the rat sitting on top of the pile of bones just ahead. He offers you the ability to join his covenant. If you join, you obtain the Crest of the Rat. Decide if you wish to join or not, then head through the corridor to the left.
Drop down into the room below -- the same room you started in -- and make sure you don't fall through the second hole into the basement. Pick up the item to obtain a Pharros' Lockstone, then drop down through the next hole onto the coffins. Make your way down to the bottom, using the coffins as a staircase.
Drop down to the stone bridge -- but not all the way down to the broken wooden bridge -- and you'll take fall damage, so make sure you're ready for it. Pick up the item at the far end of the bridge to obtain a Bleed Stone, then head to the opposite end of the bridge and look to the right to see an item below. Jump down to the tiny platform to the left of the item. Pick it up to obtain a Disc Chime.
Before you drop down to the ground floor, be careful. This is the room at the bottom of the well in Majula that leads into the Gutter. If you have not already been down there since the last time you rested at a bonfire, several enemies mount an ambush when you reach the ground floor.
If you need more information and help, the rest of our Dark Souls 2 walkthrough and complete guide can be found here.
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