This dungeon in Liurnia of the Lakes has your first opportunity to do a lot of sneaking, and it also holds many unique rewards. The boss is an old foe with a new weapon, and the rest of the mechanics should be familiar to anyone who has already finished an Elden Ring catacomb.
Grab the site of grace then continue onto the elevator. Once it reaches the bottom, step off the button, then trigger the elevator (sending it back up) and continue forward into the hallway. You’ll see an enemy walking away from you — ignore him and first deal with the enemy just around the corner to the right, who waits in ambush. Then deal with his friend, and grab the Root Resin from the corpse at the other end of the room. Continue down the next set of stairs, where you’ll find the boss door and a summoning pool. Feel free to activate the summoning pool and/or leave your summon sign — helping with the boss is a great way to learn its moveset before you face it yourself.
From the boss door, turn right and go down the stairs, then left around the next corner. Prepare yourself for an enemy in the following hallway, and take him down. You’ll find yourself in a more open chamber with some stairs leading downward. Take the stairs, then turn left and look left, down over the edge of the drop there . You’ll want to drop behind the ogre there, then back up a bit and get behind the wall to the ogre’s left . Grab the Hefty Beast Bones here, then continue crouching as you turn the corner. If you don’t see the other ogre at this point, you should be careful and go slowly, as he patrols in both directions. You’ll need to go straight for the bushes  — the ogre in the middle may alert here, but as long as you continue out of his site he shouldn’t aggro.
Through these bushes into the next small area you’ll find another item – Prattling Pate “Wonderful”. Continue forward and around the corner, take a left to enter the hallway and leave those ogres behind. Note that you may have to go around the other way, depending on the patrolling ogre’s path. Either direction is fine, just make your way to the hallway that the central ogre has his back to.
You’ll turn right, and you should immediately crouch-run towards the left-hand side of the doorway in the next room . Hide there until the ogre stops just outside the doorway, then hug the lefthand side of the doorway and sneak past him. Make sure you stick to the center of the hallway once you’re past him, as there are bones on either side that will crunch under your feet and alert him to your sneaking.
Continue down the hallway, right around the corner and then head to the ladder and climb it. Start sneaking again once you reach the top, as there’s another ogre praying to your left. Go right down the next hallway, and then prepare to be ambushed by another enemy as you reach the end of the hallway — he’ll pop out from the right-hand side. Once he’s down, you can pull the lever (which opens the boss door), then grab the Old Fang from the corpse in the corner.
Now go back down the hallway to the ogre at the statue, and backstab him. Try to take him down, but if you feel the fight slipping away from you, just grab the item he was in front of — the Page Ashes — before you die. Now we want to make our way down to the spot we first jumped down into the bushes. If you succeed in not dying, you can drop down past the lever, then turn around and continue into the hallway there. Otherwise, you’ll need to take the elevator back down, and make your way to the stairs over the pit with the ogre, then head into the hallway.
Be careful of the trap on the floor and the enemy hanging from the ceiling — dispatch him, and then prepare for the classic “hiding enemy from the right” that we’ve seen a few times already. Continue through that hallway and into the next room. You’ll see stairs on your left, and a sleeping enemy under the platform the stairs lead to. You can sneak around the sleeping foe to grab some Ghost Glovewort , and then head up the staircase, sneaking all the while.
You’ll see a Stonesword Key imp guarding a fog gate — inside is the Nox Mirrorhelm, and an enemy hanging from the ceiling, if you’ve got the key and decide to enter. Either way, wait for the ogre to go past the stairs, then stick to the left and sneak up them. There are some gargoyle imps on your right, but they won’t aggro if you don’t get too close. Enter the hallway and avoid the trap on the floor, and pull the gargoyles here into the next hallway so as to not aggro the ogre you just left behind.
Continue forward and then take a left into the next hallway, noting the trap on the ground; in the following room you’ll find three gargoyle imps. Pull them into the hallway and fight them at the entryway to avoid being surrounded. Dispatching them lets you grab the Scythe and a Grave Violet. Now go back the way you came, and try to sneak past the ogre to grab the Rune Arc that sits underneath the stairs (the ones that the Stonesword imp sits at the base of).
With that done, all that’s left is to challenge the boss, who should be a familiar foe, since it’s another Erd Tree Burial Watchdog. Note that the below-linked strategy guide is relevant (since the bosses are nearly identical) but the boss in Cliffbottom Catacombs drops the Kaiden Sellsword Ashes.
The only important change with this version of the Burial Watchdog is that he has a staff, and therefore his slam attack is slightly larger and does magic damage. It also uses this staff to summon magic arrows that encircle his head — running or rolling horizontally makes these easy to dodge, and you can also use the pillars in the room to block them.