Stone activating a creation of Pharros the Vagabond.
Pharros the Vagabond was a legend who wandered the lands, creating contraptions to help those in sincere and dire need.
The scope of his travels was so wide that the Pharros has been mistakenly credited with many inventions that were crafted by others.

This guide is for people who don't know what Pharro's Lockstone rewards are, and would like to know when to use 'em.


There are 19 Pharros' Contraptions in Dark Souls 2 on all kinds of different locations.

Forest of Fallen Giants:
Shows fake wall in room under ballista trap near Mild-mannered Pate in the Forest of Fallen Giants - Cardinal Tower bonfire.
Has Titanite Slab and Chloranthy Ring.

No-Man's Wharf:
On the second level area, in front of the house.
Creates bright light that scares Dark Stalkers away in No-Man's Wharf.

Lost Bastille:
Opens passage to Belfry Luna, accessed by the Servant's Quarters bonfire in the Lost Bastille, go down a ladder and hit the revealed wall upon placement.
One in the room with the twinblade chest, reveals room with a soul vessel, and another room which is already accessible via an elevator.

Grave of Saints:
Lowers the two different bridges in Grave of Saints.
If you put them in the sockets by the rat statues while part of the Rat Covenant, you will unleash a pool of corrosive acid that lingers indefinitely and breaks down equipment within seconds.
It will harm you as well, so don't stand in it.

Aldia's Keep:
Creates light in long hall of Aldia's Keep.

Iron Keep:
3 in Iron Keep.
2 spill out water to a small pool and lets player get wet and survive the lava to get the items and chests.
The two that add water will also heal slowly over time if the player stands in the water.
Third opens Belfry Sol and bonfire.

Earthen Peak:
In Earthen Peak before first boss, at the very bottom in a room off a poison mist floor - Has Poisonbite Ring.
Spill out poison to a small pool in Earthen Peak (area near 2nd boss, with a lot's of mushrooms and mimic chest).
Becomes water that cures poison and gradually heals after burning the windmill.

Shrine of Amana:
Just after the second bonfire in Shrine of Amana. on the floor underneath water, near where the ground drops off.
Reveals a hidden room with a chest containing Helix Halberd.

Dragon Shrine:
In the first area of the Dragon Shrine, on the floor under some boxes, behind the first knight. Reveals a hidden wall with the Judgement set and staff.

There are several (10-20) doors that can be opened in Doors of Pharros.
Most of these lockstones will activate various traps, and unleash more enemies.
The doors containing Mammoth Guards require 3 lockstones to fully open, although you can simply activate the middle one and walk underneath, saving you using the other 2 lockstones.
There are two in one of the Giant Memories (Memory of Orro - located after the pursuer fight).
The first shows an illusory wall you can attack to get through, the second (located passed this illusory wall) activates a hidden door along the wall to the right of the contraption.
This room contains the Steel Armour Set and a Fire Seed

Undead Crypt:
Behind an Illusionary Wall down the dark hole in the Undead Crypt (right after the two double shield guards).
Best to clear the area of the respawning ghosts first.
Opens a wall with a chest containing Olenford's Staff and Great Lightning Spear.
There is also a one that you get to by falling off a ledge to light a long line of candelabras in the ceiling of the crypt that illuminate much of the level.

NOTES:

Doors unlocked by lockstones reset upon entering NG+.

Pharros' Lockstone contraptions do not seem to be reset by using a Bonfire Ascetic.
However, some chests will be reset with whatever item they previously contained.
In other words, the loot respawns, but you do not need another Lockstone to access it.
Bear in mind that this does not happen for all chests located behind Pharros' Lockstone walls.

LOCKSTONE LOCATIONS:

Sold by Merchant Hag Melentia (Only 1)

In Majula,
once you have access to the Mansion, in a corpse in the Library behind the bookcases.

In Majula,
Found inside the hole in the middle of town.
The Silvercat Ring is required to survive the fall.

In Sinner's Rise,
Before opening the last gate before the boss in Sinner's Rise.
When facing the gate, in the room to your left (last door on the left)

Huntsman's Copse,
If you drop down from the wooden bridge to the isolated pillar.
Or alternatively, jump from the top of the tower above the Bridge Approach bonfire.

From middle of Earthen Peak,
one outside if you pay Laddersmith 2000 souls for it (and a twinkling titanite)

In Earthen Peak,
In a crossbow-trapped chest around middle of Earthen Peak

Farmable methods from small rats inside of "Royal Rat Authority" boss (they keep respawning till boss is dead) and also from small rats in general.

Can also be farmed from the first Mastodon Knight next to the bonfire in Doors of Pharros.

Near the beginning of the Shaded Woods on a hill

In the Shaded Ruins,
on a corpse on the second story of a ruined building behind the Giant Basilisk.

Starting item for Explorer

In The Black Gulch,
Hidden Room Bonfire, a corpse in a pot.

In Aldia's Keep,
Behind one of the wooden shelves in the room filled with bright green glass containers. The room before the hidden bonfire.

In Dragons Aerie,
between the second and the third guardian dragon, drop down the ledge, a corpse holds the stone

The Rotten,
Cutting off one of its arms. (Both arms can be cut off)

Walkthrough towards the Contraptions.


FOREST OF FALLEN GIANTS:
Proceed through the area near the Cardinal Tower Bonfire until you reach Pate.
Make a right near him to spot an archway with some ballistas.
Step inside, then back out quickly.
The undead soldiers will fire the ballistas, then pursue you.
Take them out, then head inside.
On the lower level is the Pharros Contraption; use your lockstone to reveal a secret room hidden by a fake blue wall. Inside is a pair of chests with a Titanite Slab and a Chloranthy Ring.

NO-MAN'S WHARF:
There are several sets of stairs embedded in a hill in this area. When you ascend the first set, take a right.
Take out the bandit and his dog, then make another right to find this contraption on the ground.
This won’t net you any treasure, but it will illuminate the entire cavern, making navigation easier and scaring the poisonous enemies indoors.

THE LOST BASTILLE (1/2):
This is found directly beneath the Servants' Quarters bonfire.
Climb down the ladder in the corner to find it, then use a lockstone to reveal a fake blue wall.
Head through to gain access to a new area, Belfry Luna.

THE LOST BASTILLE (2/2):
Found in The Last Bastille. When proceeding from the Servant's Quarters bonfire, you'll have to jump across some rooftops.
Drop down, take out the dogs, and head down this alleyway.
Climb the ladder, hop through the window, and take out the mini knight on the other side.
Continue into the next room, and check the wall to your right to find another contraption.
Use a lockstone to reveal two fake blue walls.
Behind one is a Soul Vessel; behind the other is a Wilted Dust Herb.

DOORS OF PHARROS:
Warning: ALL doors of pharros contraptions creates traps meant for the Rat King Covenant.
There are small prizes behind some, but you should not waste your lockstones here.

EARTHEN PEAK (1/2):
Upon entering Earthen Peak, you'll be in a chamber with poison water below.
Step down the stairs, then follow the hall to the right, then take the first right.
Take out the poison enemies here, then look along the wall for the contraption.
Using a lockstone reveals a fake blue wall.
Behind it is a chest containing the Poisonbite Ring.

EARTHEN PEAK (2/2):
Climb Earthen Peak until you reach the poison pool before the fog gate.
To the right of the gate is a lit passage; follow it, then make another right.
In here are several poisonous enemies and pots, plus a contraption.
Use a lockstone to create a pool of poison; once you set the windmill aflame, this pool becomes water, which heals poison and restores health.

IRON KEEP (1/3):
You can find this after lowering the first bridge in Iron Keep.
Cross over, then make a right.
From here, you can leap to a lower ledge near the lava.
Do so, then enter the small room and climb the ladder.
Take out the knight here, then use a lockstone on the contraption against the wall.
This creates a pool of water.
Standing in this will be giving you some resistance against the fire and lava in the area.

IRON KEEP (2/3):
When you enter the second area of Iron Keep (with all the walkways), make an immediate left to find a contraption along the wall.
Use a lockstone to reveal a fake blue wall.
Bust through to find a ladder to a chest containing a Thunder Quartz Ring +1.
This also opens the passageway to Belfry Sol.

IRON KEEP (3/3):
To get this, first head to the second section of Iron Keep (with the walkways and greatbow-wielders).
Take the ladder in the back, then follow the stairs to a second ladder.
This leads you to another Pharros' Contraption.
Like the first one in the area, this creates a pool of water you can use to temporarily boost your fire resistance.

GRAVE OF SAINTS:
Most of the Pharros' Contraptions found on the path to the Grave Entrance bonfire are meant for the Rat King covenant; they merely activate traps.
Only the two directly across from bridges are useful to you right now.
They lower their respective bridges, giving you access to a room where you'll find a corpse holding the Whisper of Despair hex.

SHRINE OF AMANA:
This is just across the water from the Crumbled Ruins bonfire.
Place a lockstone reveal a fake blue wall. Bust through to find a chest containing the Helix Halberd.

UNDEAD CRYPT:
This is found in the room where you drop into, and bells ring.
Look for a spot on the wall with no bevel; interact with this to reveal a fake wall.
Behind this is a Pharros' Contraption.
Use a lockstone to reveal another fake, blue wall.
Smash through to find a chest containing Oleford's Staff and the Great Lightning Spear miracle.

ALDIA'S KEEP:
After heading up the stairs to the top floor, you'll find a pull-chain on a dragon statue.
Pull it to open the next room, head inside, and make an immediate right.
There's a contraption along the wall here.
Use a lockstone to light the torches in the hall, making the area a little easier to navigate.

DRAGON SHRINE:
Just up the slope near the Shrine Entrance bonfire is this archway; head underneath to find a contraption.
Use a lockstone to reveal a fake blue wall, then bust through to find a chest containing the Staff of Wisdom and Judgment Armor (Full Set).

MEMORY OF ORRO:
You'll find this inside the Memory of Orro, accessed by using the Ashen Mist Heart on the fallen giant beyond the Pursuer boss area.
Inside, take the left path up to find a room with ballistas and Hollow Soldiers.
You'll find a contraption here too.
Use a lockstone to reveal a fake blue wall, then bust through to find a second contraption and chest.
The rigged chest contains a soul, and the other contraption is a trap.
You'll also find a fake wall in here that allows you to obtain the Steel Armor (Full Set).

The Rat covenant is dedicated to protecting the sanctity of the Grave of Saints and Doors of Pharros location.
Trespassers are handled by Rats and honorary Rats (players who've joined the covenant).
This covenant is PvP based but with an emphasis on protecting "your turf."
This is accomplished through a summoning mechanic specific to this covenant.
The player, while in the covenant needs to wear the ring Crest of the Rat while in the Grave of Saints location (the bonfire near the boss fight, Royal Rat Vanguard room and Rat King room do not count as viable summoning areas) or the Doors of Pharros location (specific summoning areas unknown).
If another player enters the summoning zones in THEIR world, they have a chance to be automatically summoned to the world of a covenant member for battle.
What this means is that the trespasser (non covenant player) must do battle in the home turf of the covenant member.
This yields numerous potential bonuses to covenant members.
The covenant member can summon enemy players while they are hollow.

Firstly, covenant members benefit by all mobs (several hollows and numerous large rats) becoming allies at all times.
A covenant member will NEVER be attacked by mobs while in the Grave of Saints.
However, trespassers must face all mobs that aggro in addition to the covenant member.
Mobs do still follow the respawn rules so covenant members can find themselves without backup if their buddies are killed too many times.
Additionally, the Grave of Saints is littered with Pharros' Lockstone faces which may be used to alter the environment.
Once placed, a stone cannot be removed, however placing stones allows the covenant member to alter their turf and lay traps for invaders. Two bridges for instance open a smaller secondary area that can be used to loop around the two primary walkways that make up the Grave of Saints. A group of additional rats can be a trap to lure trespassers to in this room.
Rat statues with urns can be activated by Pharros' Lockstone as well on the upper walkway.
They will pour acid on the floor which damages armor very quickly.
The covenant member IS affected by this but they have the luxury of knowing which pools are active.
Pools can be jumped over but this requires very precise timing.
A ladder connecting the two walkways has a filthy looking waterfall when a Lockstone is used nearby.
This does not appear to harm either party but can be used to hide behind and lure the trespasser into more rats unknowingly.
If either party is using a torch it will be extinguished.

A trespasser will be summoned as a "Gray Spirit" and will always spawn at the entrance of the Grave of Saints.
This means that they will encounter the large group of rats and several hollows at the beginning of the level (until they stop spawning) and of course the Rat King covenant member if they feel like being mean.
If a trespasser kills mobs they remain dead until the covenant member rests at a bonfire (there are two easily accessed in this area). Trespassers CAN use a Black Separation Crystal to separate themselves from the world.
This is dependent on being given enough time to use this however as the covenant member is given a warning that a trespasser is being summoned well before they arrive.
In other words, there is no reason that the covenant member can't be waiting for the trespasser if they choose.
If the covenant member wins they will gain a Rat Tail which can be offered to The Rat King to further one's devotion to the covenant.
If the covenant member loses they must find their blood stain and suffer the normal penalties of dying.
Recovering the stain is of course not an issue as nothing in this area will be hostile to the player.
There is also a 10-minute time limit to killing the summoned player, if it runs out, they will return to their own world.
In addition, there seems to be a three minute delay before another invader could be summoned.

REWARDS:
If you are in the Rat Covenant and win you will receive: 1 Pharros' Lockstone, 1 Rat Tail.
If the 'trespasser' manages to make it to the end of the area they are given 1 Pharros' Lockstone, as well as returning to their world in front of the bonfire at the end of the labyrinth.

Additional Information:Rat King covenant members can also summon and engage in PvP in the Doors of Pharros area.
Enemies beyond the Gyrm's Respite bonfire will not attack the player, and similarly to the Grave of Saints, traps can be created by placing Pharros' Lockstones.
Upon defeating a summoned gray phantom, the covenant member is awarded with a Rat Tail and a Pharros' Lockstone, along with souls from the opposing player.