Eliminate the guards that drop down to greet you when you enter Sinner's Rise, then walk over to the corner and through the doorway. On the right is a ladder that you can take to reach a bonfire. The staircase on the left takes you down to a room with several archers. The safest thing to do is take out the archers first, but if you're confident in your abilities, head to the bonfire via the ladder and light it, and then deal with the archers.
Just before you reach the bonfire, there's a doorway on the right where you can find a Large Soul of a Lost Undead. Inch your way into the door and along the ledge because it's narrow, and you don't want to fall off. After setting the bonfire ablaze, go back down the ladder and continue along the path, past the room with the archers, to find a Human Effigy item at the end.
Go back to the archer room, and take the elevator in the middle all the way to the bottom. There are five Lacerating Knives on the second to last floor that you can jump to before you reach the lowest floor. You can get them on the way down, or the way up. If you get them on the way up, once you've grabbed them, drop down to the lowest floor again (making sure you don't fall into the water), and then call the elevator.
Head down the ramp and into the water. There's a large enemy to the left, which you can kite back to the elevator room, and then take the elevator at the last moment up to the next floor. It'll come at you, but fall into the water below. If you can't get the timing right on this, a range weapon is your best bet. And if you're not good at that, goad the enemy into attacking, and then run in and whack it while it's recovering. Rinse and repeat.
To the far right, just beyond where the enemy was, is Sublime Bone Dust. Move over to the opposite side of the area to the next enemy, and use the same tactics are behind. In the corner behind where the enemy was is a Large Soul of a Nameless Soldier.
Another large beast lurks on the other side of the area. Take it out first, and then move to the right, where you'll find a zombie-like enemy that falls near you to inflict damage. Kill it before it does, and then go upstairs and to the right. Go past the first the two cells, and take out the sleeping enemy at the end of the path. Go to the opposite side and eliminate the other sleeping enemy.
Go back downstairs to the water and continue along the path. The cell on the right in this lower section has a one enemy, and the left one has two. Inch towards the right-hand cell and get the enemies attention, then kite it back up before taking it on. Once you've killed it, return to the left and inch forward until you alert the first enemy, and then back out and kill it as fast as possible. You should have enough time to eliminate it before the second one emerges from the cell.
Now that area is clear, head to the last cell on the right and kill the final enemy. Take the Soul of a Proud Knight and Pharros Lockstone from the last cell on the left, then pull the lever at the end to open the gate. Head to the left of the mist and take the Radiant Life Gem that's in the corner, and then head into the mist.
Boss Battle: How to beat The Lost Sinner
If you have a shield that absorbs 100 percent damage, you're ready for this fight. If not, it's going to be tough. The Drangleic Shield is one such item, and you can get that by defeating the Pursuer. Walk past where you engage him, and drop down through the large hole in the ground. At the bottom is a body that holds the entire Drangleic set of items, including the Drangleic Shield.
You need this defensive weapon to help The Lost Sinner's fast and frequent attacks. There's usually only time to get one or two hits in after an attack before you need to block, so a good shield is key.
The fight is in a dark area, and some players might need to turn their brightness up if they have a dark picture. That'll help you keep track of the boss. If you already have the Bastille Key, you likely won't need to do this.
When the fight starts, The Lost Sinner charges. Block or evade his initial attack, stay as close to him as possible. He uses two consecutive attacks that cover a circular area in front of him, and occasionally follows up with a straight attack that you can easily avoid by dodging left or right. He sometimes uses a single forward stab that can be avoided in a similar fashion – and very occasionally jumps over you and then does the attack. Again, dodge left and right.
Keep close to The Lost Sinner at all times, and make sure you always have at least a little bit of stamina so you can block his attacks without taking damage. Don't run yourself out of stamina, and don't let the boss move too far away from you. Just keep circling until he uses his two circular attacks, jumps or stabs and then run in for no more than two hits. In the case of the stab, unless you time it perfectly, you'll get no more than one hit in before leaving yourself vulnerable.
Keep doing this, and eventually you'll prevail. Open the double doors at the far end of the area and go downstairs into the next room, and open the coffer to find a Fragment Branch of Yore and an Elizabeth Mushroom. The Fragment Branch of Yore restores petrified living things and works in many areas, including the Lost Bastille above you.
Set ablaze the primal bonfire in the following room, and you'll get a ride back to Majula. Next up, there's the Belfry Luna, or if you're a mage class, you can unpetrify the wizard Straid and get a few nice spells, or you can use the Fragment Branch of Yore to clear the path near Majula.
Mages can opt out of the alternate Majula path for now, and instead travel back to the Sinner's Rise and take the ladder down. Cross the bridge to the Lost Bastille, taking out the guard on the far side of the bridge, and the two enemies in the room at the end of the bridge. Go upstairs and lure the enemies downstairs one at a time until you've cleared the area. Use the Fragment Branch of Yore to return the petrified Straid to life. Speak with him and he teaches you the mock gesture, and allows you to purchase some handy spells.
Head to the Lost Bastille (Servants' Quarters) bonfire, and tidy up your items before moving into Belfry Luna. Go upstairs and through the door. Head over the makeshift bridge and to the right. When you reach the next room, enter the doorway then go to the left and all the way to the end of the path where the wall is broken. Drop down onto the roof, then jump from the wooden structure to the opposite rooftop.
To the left of the latter is a Large Soul of a Nameless Soldier. Maneuver down to the area below and deal with the four dogs. Make sure you don't to hit the well or you'll have to deal with even more enemies. Enter the room at the end and take out the guard there. Go into the cell in the corner, then immediately head back out and wait for the two enemies to come out into the open room and eliminate them.
Return to the cell and you'll find two Flame Butterflies. Head back into the main room and smash the wooden barricade that blocks the opening in corner, and you'll access the courtyard near the entrance to the Lost Bastille. You can choose to fight the White Knight on ladder in the courtyard, and your efforts will yield a low level Heide Spear, but a decent selection of souls.
Return outside where you fought the dogs, and enter the door directly in front of you. Fight the three guards inside, and then climb up the ladder to the left and look for a Green Blossom and a Large Soul of a Nameless Soldier.
Once again go back outside, and follow the alley to the side of the building to its end, where there's a ladder. Climb up and through the window into the building. Roll to destroy the boxes in front of you, and you'll reveal a small passageway. Kill the two guards in the next room and open the chest on the left to obtain a Bone Staff.
Note – don't use the Pharros Lockstone at the entrance, because you'll end up in an area that you've already explored. You've already done everything you can here (for now), so head back to the Servants' Quarters bonfire and go down the ladder near the corner of the room.
Kill the dog below, and use the Pharros Lockstone in the center of the wall. Attack the ghostly image that appears on the adjacent wall to reveal a corridor behind it. That grants you access to Belfry Luna.
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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