Of all the mandatory areas that one must traverse in Lordran to acquire the 4 Lord Souls, the New Londo Ruins can be among the most challenging thanks to the sheer amount of hazards and dangerous enemies that lurk in this partially sunken city.
Even Dark Souls veterans dislike having to venture here to slay the Four Kings, as the ghosts and darkwraiths make the already dank location even more troublesome. Due to the unpleasantness, most Chosen Undead choose to only collect the essentials before heading down into The Abyss to face the spectral rulers of this damned and damp area. Because most don't linger here, some useful things can be missed, so the next time one travels to the New Londo Ruins, keep an eye out for these missable treasures.
10 Ingward's Anti-Curse Services
Players need to meet this red-robed sorcerer in order to acquire the Key to the Seal, which is one of the items required to make one's way toward the Four Kings, however, that is not the only reason to chat with Ingward.
In addition to selling the sorcery spell Resist Curse that reduces curse status build-up and Transient Curse consumables which allow one to hit ghosts, Ingward also can cure one of the curse status effect. This is only otherwise possible with the expensive and rare Purging Stone items, but good ol' Ingward will only charge a single liquid Humanity (tracked by the large number next to one's HP bar) to remove one's affliction.
9 Fire Keeper Soul
Out of the unique souls in this dark game, those of fire keepers are far and few in between. Since they increase the healing power of one's Estus Flasks, they are always worth picking up, even if the cost is death. This is very much the case for the one located in the New Londo Ruins.
Through a shattered series of archways, there will be an illuminated item across a thin, partially submerged path. As if the threat of drowning isn't enough, this glowing item, the Fire Keeper Soul, is also guarded by a pair of pesky ghosts who only appear after one begins crossing the treacherous path.
8 Cursebite Ring
Since curse is arguably the worst out of all the status effects that one can be afflicted with, players should definitely pick up the Cursebite Ring while in the New Londo Ruins despite it being a bit awkward to obtain.
Down a corridor lined with grabby-handed ghosts, there will be a ledge at the end overlooking a steep drop where there will be a lootable corpse. Upon this body is the Cursebite Ring, however, be warned that on this ledge is yet another annoying ghost who will immediately attack the Chosen Undead.
7 Very Large Ember
In order to upgrade one's weapons to +15, the highest level possible, players will need to find the Very Large Ember and bring it to a blacksmith. Of course, since this item is in the New Londo Ruins, it will be a bit tedious to find, however, the Chosen Undead will know it when they see it as it is located in a chest.
This chest is upon a ledge that is near to some stairs and can only be accessed after lowering the water level of this flooded location.
6 Mass Of Souls
A monstrosity that is among the most disgusting of all Dark Souls enemies, the Mass of Souls is a miniboss; a particularly tough and unique enemy, that haunts the lower areas of the New Londo Ruins. Following one's draining of the lower area, the player will find this horrid beast oozing about an open courtyard close to 3 darkwraiths.
Most simply run by this slow fiend as it does not drop anything except souls, making the time to fight it not worth the effort for most, however, it drops 5,000 souls, meaning it could be a decent target for those needing to level up.
5 Titanite Chunks
Most don't really stick around to tangle with all of the darkwraiths lurking in this deep, dank area, and for good reason. These abyssal knights will take every opportunity to try and suck out some humanity from the Chosen Undead, however, these enemies are arguably the best to farm for Titanite Chunks.
At the base drop rate, before the effects of any rings or armor, darkwraiths have about an 8.5% chance to drop one of the much-sought-after upgrade items as well as a tiny chance (0.32%) to drop 2 chunks at once.
4 Titanite Slab
In addition to dropping Titanite Chunks, darkwraiths have a very small chance (0.21%) of dropping the incredibly rare Titanite Slabs, which are used to upgrade any given item to their final level. Since there are only 4 guaranteed slabs to be found in the entire game, those looking to increase their max-level weapon collection will need to do a bit of farming.
In order to make this harvesting (slightly) less tedious, it is highly recommended to increase one's Item Discover stat (base 100) by equipping the Covetous Gold Serpent Ring (+200 Item Discovery) and having 10 humanities stored (+110 Item Discovery). The highest Item Discovery value is 410, which quadruples the chances of a Titanite Slab dropping, though this still isn't even enough to raise the drop rate to above 1%, so good luck!
3 Dark Hand
The last of the important drops that can be gained from felling darkwraiths is the Dark Hand. This sinister armament, classified as a fist weapon, is short-range yet possesses a powerful unique ability. While equipped in the right hand, players can use a strong attack to initiate a grab move that will suck out a Humanity from an NPC or human player.
This is identical to how the darkwraiths try to use the Dark Hand on the player, and it can be very satisfying to pull off on other people. Furthermore, despite lacking stability, this weapon can be used as a shield in the left hand. The drop rate for acquiring a Dark Hand from a darkwraith is 1% before Item Discovery boosts.
2 Jagged Ghost Blade
There are significantly better methods of dealing with the ghosts and banshees of the New Londo Ruins than taking them out with their own weapon, however, if one wants to fight fire with fire, the Chosen Undead can potentially get the Jagged Ghost Blade as a drop from the fiendish spirits (1% chance before boosts).
This curved sword is the only weapon in the game that can naturally harm the spectral beings of the flooded ruins, which can help one save on souls and alleviate having to purchase Transient Curses from Ingward.
1 Darkstalker Kaathe
The more sinister of the 2 primordial serpents that the player can meet in Dark Souls, Darkstalker Kaathe is the leader of the Darkwraiths Covenant, a catalyst for the alternate ending of the game, as well as the one who tempted the Four Kings down the path that led to the flooding of New Londo.
Kaathe appears in The Abyss after the Four Kings are defeated, but only if one has not placed the Lordvessel and did not agree to help Kingseeker Fraampt.