Head down the stairs to the left to find a bonfire. Light it, then head back up the stairs and across the bridge. Kill the two enemies at the end, then head through the large doors and dispatch the two enemies up the stairs.
Continue up the next flight of stairs to engage three more enemies. The third enemy is off to the left pelting you with arrows, so it's best to lure your opponents back down the stairs and fight them one or two at a time. Take down all three enemies, then head up the stairs where the archer was positioned. Interact with the wall to unlock a hidden door. Head inside to find 20 Fire Arrows behind the catapult.
Go through the doorway in the hidden room then interact with the wall on the right to find another hidden door. Take down the enemy on the other side, then pick up the Pharros' Lockstone in the corner. The pots in this area offer marginal fire resistance if you roll into them. Use this in combination with any other fire resistant item or armor piece, then drop down and pick up the Iron Key that sits in front of the fire spout below. The fire still does a fair amount of damage even with resistances, so grab the key as quickly as you can and get out.
Head back down the stairs to the hallway on the left. At the end of the hallway is the merchant Magerold. Speak with him and check out his wares. You can purchase a Fragrant Branch of Yore here if you're in need of one.
Make your way back down the hallway, up the small stairs at the end and then up the next set of stairs to return to your last point of progression. Head through the doorway and follow the path around to the left. Take down the enemy, but watch out for the elevated archers to the front and back. Continue down the stairs to the right, then take down the enemy and pull the lever in the corner to lower the bridge. Don't worry about the door here as it just leads to a room filled with flames at the moment.
Move back up the stairs and then to the left to cross the newly lowered bridge. Drop down to the path at the end, then head to the right to find a coffer that holds a Zweihander sword. Head to the opposite end of the path, take down the enemy and enter the mist to fight the Smelter Demon.
Boss Battle: Smelter Demon
The best way to take down the Smelter Demon is to equip a shield that absorbs 100 per cent damage, and light armor so you can strafe around the Demon quickly. The Demon doesn't have a wide range of attacks, but you need to be able to either quickly strafe to avoid them, or dodge effectively more often than not. If you can do this, the fight should be relatively straightforward.
When the battle begins, the Smelter Demon's body is on fire, but the flames are fairly small. If you stand right next to its body, you may take minor fire damage, but it's nothing to be too worried about. Once you've inflicted enough damage, however, it pauses to turn up the heat. At this point, you don't have to be standing quite as close to take damage, and you take a little more damage compared to the start of the fight. Inflict a bit more damage to get the Demon down to around 50 per cent health, and it sticks its sword in its body to engulf the sword in flames.
Throughout the entire fight, the Demon uses a small set of attacks. It has a three hit combo that consists of two horizontal attacks followed by a vertical attack that can be grounded or follow a jump. The jumping variant is more difficult to avoid, and the Demon may sometimes create a burst of flame following the jumping attack.
The jumping attack can also be used by itself, and the flame burst doesn't always follow the jumping attack in either situation, but you have to always assume it will occur in order to avoid the damage. If you're close to the Demon during the flame burst, you'll take considerable damage. As the size of the flames on the Demon's body increase, so too does the range of the flame burst. By the end of the fight you'll need to be roughly halfway across the battlefield to avoid it.
If you stand a moderate distance away from the Demon, it uses a linear attack that breaks your guard. However, the Demon doesn't follow it with anything, so you have time to regain stamina and avoid taking damage. Once the sword is on fire, this attack shoots flames in a linear manner. It can still be avoided by sticking close to the Demon or dodging to the left or right with proper timing.
Your main attack pattern should be to stick close to the Demon, circling it as quickly as possible. If you're light enough, you move fast enough to block the first horizontal attack of the three hit combo, then the second attack will completely miss, and sometimes the third attack won't happen at all. As soon as you see the Demon pause, hit it with two or three attacks depending on the speed of your weapon.
More than like you will not inflict significant damage with each attack, and you'll constantly take damage from its flaming body. This is a battle of attrition. If your health gets low due to the Demon's flaming body, take the next opening to use a healing item or ability. As long as you're evading the Demon's attacks and staying on top of your own situation, it will go down before you do.
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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