Make sure to grab the Leyndell Catacombs site of grace, and start going down the stairs. Past the room with the locked door to the boss room, you’ll reach another room with an altar in the middle, and several enemies above you. With how slow they are, you don’t have to deal with them at all and you can simply just run through and go up the next set of stairs.
There, the path to the right will take you deeper into the dungeon, while the room in front of you will have a corpse with a Ghost Glovewort  as well as a couple of enemies praying in front of it, and a third one hiding to the right of the doorway.
Once you’re ready, go right and you’ll be in a room with 3 enemies that will explode if you come close. You don’t have to fight them, and all you have to do is come close enough for them to get upset before running away until they explode. Deal with these guys and continue further, into the hallway with the fire trap. As usual, either run to the hallway to the right to wait out the flames or use a ranged attack to disable the fire trap, and enter its room. There, after dealing with the small enemy trying to bother you, grab Grave Violet and jump on top of the disabled fire trap while using a heavy jumping attack to re-enable it, and ride it to the platform above.
There, in the room in front of you, murder the Omen standing in front of the altar and steal the Crucible Scale Talisman on top of it. This being a dead end, go back down, disable the trap once more and this time go northwest, up the stairs. There, deal with the Omen on your way, grab the Grave Glovewort  next to where he was and continue further, into a room overlooking a familiar looking altar. Make sure to grab the Golden Rune  hanging from the ledge before jumping down and grabbing the Grave Glovewort  from the altar.
While this area looks very similar to the start of the dungeon, it’s actually an entirely different area. With that in mind, take the doorway northwest of where you are to find two different paths. If you go right, you’ll be able to grab 4x Root Resin, while going left towards what looks like a boss room will allow you to grab a Ghost Glovewort  and a Golden Rune , though you will have to defeat 2 Omens, one hiding to the right of the doorway and another in the back of the room, in front of the Golden Rune .
Once you grabbed everything you wanted (no shame in skipping the Omens), go back to the room with the altar and take the stairs to the southeast. At the top of these stairs, you will see a very familiar looking room, and a hallway leading to a firetrap. This time however this area will be completely empty, but make no mistake, you’re on the right track here.
While riding this fire trap to the platform above it is the way forward, we can make a small detour to grab some upgrade materials. Take the turn right instead of going to the fire trap room, and you’ll find yourself in a room with a Grave Glovewort  next to the stairs, and what looks like a sad Omen.
Grave Glovewort (Sad?) Omen
Help this guy by putting him out of his misery and continue forward until you reach yet another room overlooking an altar. Jump down, and the only path forward will be southeast, which will lead to some more familiar looking rooms and hallways. This section however will be a bit different: there will only be a few enemies and there won’t be a fire trap. While you can pretty safely pick up some flowers before heading to the window, be careful as you enter what used to be the fire trap room as an Omen will jump down from the platform above. Once you got everything, jump out of the window and you’ll find yourself in the room where the sad Omen used to be.
Grave Glovewort Grave Glovewort Grave Glovewort Way back to the sad Omen
As you jump down, turn around since we have already gone through the area on top of the stairs, go to the nearby fire trap room and use it as an elevator to reach the platform above.
Enter the room the nearby, and this time around, you will see a doorway northwest leading to a couple of imp enemies and a Grave Violet. Past these imps, you will finally reach a different-looking part of the dungeon. Go down the stairs these imps were guarding and go down the ladder at the end of this path. After going through these last hallways you will reach a room overlooking the altar from the start of the dungeon. Grab the 2x Sacramental Bud, interact with the lever to unlock the path to the boss room, and jump down before heading northwest towards the entrance of the dungeon and the boss room.
Make sure to rest at the site of grace to replenish your flasks, and once you’re ready, head to the now-unlocked door leading to Esgar, Priest of Blood.