Right. Pick up the Soul of Nadalia, Bride of Ash dropped by the idol, then yank on the lever in the corner to open the iron door in front of you. There's another bad guy just beyond, so take your time, then pass through the doorway, bear left and move down the incline towards another item. Two more Axe Demons will emerge behind you as you approach it, but you should be getting used to dealing with them by now, so do your business and then pick up the five Lloyd's Talismans you were coveting. Go back up the hill, past the door, down the stairs beyond and through the door onto another balcony.
There are more enemies here and these guys are holding explosive barrels. Helpful. Ranged attacks are your friend. Once you've blown them up, go to the end of the room and stick to the left side until you find a ladder. Go down it and edge towards the stairway you see. This should alert the enemy in the next area, who will move in to fight you. However, he won't flinch as you attack, so be extra careful, blocking with your shield or dodging as appropriate.
With that guy down, tiptoe down the stairs. Halfway down, look left and there should be another barrel-clutching bad guy next to a flaming statue. Deal with it with a ranged attack now and you won't have to worry about it later, but there are a couple of others near the statue so beware. If you have any throwable objects (Firebombs, etc), you can chuck those over the gate to hit these enemies - it may not kill them, but it will wake them up, making it easier to blast them when you head round the corner.
When they're dead, grab the two Goldenfruit Balms at the bottom of the stairs. Then move into the next room and through the door next to the flaming statue. Down the next ladder, kill the enemy, then step to the right of the ladder. There are three more enemies below. You should be able to hit one with a ranged attack, which is good, because it has Firebombs. They won't hit you if you're careful with your footing though. With this guy down, move down the ladder and wait for the other two to move away from the bottom of it before you get there.
The red invader will chase you up the ladder while the other guy will not, so use this to your advantage to separate them, dealing with reddy up above before coming back down for his friend. The invader has throwing knives and a whip, which gives him impressive reach, and he likes to stun at close range so he can pile in for heavy damage. In short: be careful. Wait for him to start lobbing knives, then close ground and you should have time for 2-3 quick attacks or 1-2 slower ones. Quick ranged attacks are also useful here, giving you time to dodge the knives.
Once he's down and you've dealt with his friend below, open the nearby chest for a Caestus +8, go through the adjacent entrance and down more stairs. Then look in the room on the right and you'll see another bonfire. Phew! Don't worry about the statues in here for now.
Go up the small stairway ahead and take a left. There's a door here that doesn't open yet, but you can see into the room where it goes, revealing a couple of enemies with bows amidst various flame traps. You can deal with them using ranged attacks from here quite safely if you're smart and stay close to the railing, although if you're happy to brave the open ground there's also a chest with three Twinkling Titanite. Just wait for an arrow to hit the railing, then leg it to the chest. You can also kill the enemies here cheaply by alerting them to your presence and then manoeuvring into the passageway where the railing starts, which kites them into nearby flames, consuming them.
Go back to the bonfire room, go straight ahead and round the corner on the right to find a fog door. Go to the left and into the first alcove and there's a ladder on the right. Watch out for the baddy with the explosive barrel at the foot of it, although he should drop through a trap door just once you reach the lower area. Go out of the alcove at the bottom and hang a right. Into another passageway you go, with a door to open at the end. Take a step back as soon as you open it though, ideally with ranged attacks on standby, because there are two more barrel-huggers waiting for you. You can probably one-shot both of them.
Beyond them is a ladder with three Radiant Lifegems next to it. There are a few enemies in the area below, including the explosive barrel jerk who fell through the trap door. If you take your time, you can stand on the left of the ladder (careful of the trap door) and hit the explosive enemy with a ranged attack when he saunters into view. Otherwise, there are four Axe Demons and a Giant Club Demon that shoots fire from its body, plus an Ashen Idol. You can take them all out from the hole by the ladder if you're patient, although you'll need to jiggle around on the ladder to get them to play ball. But hey, you weren't in a rush, were you?
Oh, you were. Well, in that case, go down and get stuck in. Save the Giant Club Demon for last, though, and manage your distances carefully. Keep them at a decent range and they'll have to fall back on ranged attacks, which is easier than coping with multiple close-quarters attacks in parallel. Once you get to the Giant Club Demon, pay close attention to the fire that spews from its body - you should be able to time your movements to avoid it - and watch out for the occasional burst of pace. Keep moving and try to stay behind it.
And hey, there's also a bad guy in a cage nearby, above the room, launching firebombs. You know, because. They won't reach the whole area though and he's a doddle to deal with using ranged attacks, especially if you save him for after the nearest Axe Demon and Giant Club Demon. A good rule of thumb while he's alive is not to venture past the item on the ground.
With all those guys dead, grab the Flame Quartz Ring +3 (boosting fire defence) near the bottom of the ladder, then head over to the Ashen Idol in the corner. This is the same as the very first one you met, coming to life when you get to the dune just in front of it. Dash in after it spews its first burst of lava, insert a Smelter Wedge and pocket your latest Soul of Nadalia, Bride of Ash.
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