Wandering in the Dark

Wandering in the Dark is a main quest in The Witcher 3: Wild Hunt. In the search for Ciri, Keira Metz tells Geralt of an elven mage who visited her. The mage had clues to Ciri's whereabouts, and invited the sorcresses to an old ruins site where more information could be discovered. When Geralt and Keira begin to explore the ruins, they discover that The Wild Hunt is on the same trail.

Quest Description
"Finding Ciri in Velen had proven harder than tracking a swallow on a rainy day. According to Keira, an elven mage had been tracking this particular swallow as well. Had he found her?  Did he know more about her fate?  Geralt knew he had to find out, and Keira, well, she had unfinished buisness of her own with the mage.  And so the witcher and sorceress set out together on a journey into darkness to find the mysterious elf's underground hideout."

- Dandelion

Meet Keira
If Geralt does not immediately go with Keira after meeting her in the previous quest, Hunting a Witch, he will be given the objective to meet with Keira at the entrance to the elven ruins just Northwest of the Byways signpost.

Follow Keira
Geralt and Keira arrive outside the cave where Keira was suppose to meet the elf. They enter the cave and once they reach the base of the steps, they see the Wild Hunt on the other side of the broken bridge.

Go Through Keira's Portal
Keira opens a portal to get to the other side of the bridge, but as they enter the portal, the two are teleported to different areas of the cave. ''Note: If Geralt ignores the portal he will remain in the main chamber and will begin his search for Keira from there. This may be preferable to going through the portal where you will be teleported to a cavern distant from the main chamber and you will have to fight, defeat nekkers and foglets, your way back to the main cavern before searching for Keira.''

Find Keira
Using witcher senses, Geralt is able to see where Keira's calls for help are coming from. Fight through the monsters to make it back to the original chamber and then use witcher senses to find and follow Keira's shouts. Geralt finds her cowering from rats and a couple of rat nests nearby.

Destroy the Rat Nests
Destroy the rat holes with either bombs or Igni spell to receive 100XP for each destroyed nest. Keira will explain to him that there is something distorting her teleportation and demand that they leave the caverns. Use any dialogue option to convince her to stay and pursue the Wild Hunt.

Explore the Elven Ruins
Continue the search, and Geralt will find a projection message from the elf. From the message and Geralt's knowledge of Ciri's sword name, "Zireael" or elven for "Swallow", they know to follow the picture of a swallow painted in the cavern to find the next projection. Geralt is awarded 100XP at the completion of this objective.

''Note: You can disperse the toxic clouds made by the mushrooms native to this cave using either Aard or Igni, the latter causing a large explosion of fire. There is a flooded corridor that leads to a loot chest off the main cavern that was an elven dockside at one point.''

Search the Chamber
This projection makes a reference to Kelpie, a sea monster and the name of Ciri's horse. There are two symbols nearby, one of a dog and the other of a kayran. The dog symbol will cause an explosion when activated that will damage Geralt. The kayran symbol will summon a pair of wraiths disguised as clones of Geralt and Keira.

Find Kelpie & Rejoin Keira
The symbol of a horse is located below in the octagonal pool, so Geralt will have to jump down into the pool to investigate. Geralt follows the clue and finds another horse symbol after passing through a flooded passageway. The second symbol activates a door in the main chamber where Geralt left Keira.

Explore New Chambers & Enter the Portal
They find the portal in the cave that has been distorting Keira's teleportation, and activate it, landing in a new room.

Fight the Guardian
Inside this new room is a lurching golem that must be fought. Keira does a decent job of stunning the golem, keeping him at bay if Geralt needs time to heal or regenerate stamina. Elementa Oil or Dimeritium Bombs are most effective against the beast. Once the golem is defeated, continue up the stairs and the down the passage.

Continue to Explore
The first doorway on the left will lead to another portal which will teleport Geralt and Keira to the other side of the bridge which they had been trying to reach initially. If Geralt continues further down the hall and takes the second door on the left it will close behind him and a Gargoyle will appear which Geralt will have to defeat to escape the room. There is some loot in this room, so it might be worth fighting the gargoyle even though it is totally optional.

Note: The Gargoyle is weak to the same things as other elementa, elementa oil and dimeritium bombs as well as Quen Sign.

Follow the Wild Hunt
Rush to catch up to the Wild Hunt, and find the cave guardians frozen by the riders. The duo catch up to the Wild Hunt, only to have their navigator, teleportation mage, to open three portals to the White Frost, causing a blizzard.

Keep Close & Kill the Creatures
Keira will shield Geralt as the two walk through the room. Geralt must protect Keira from Wild Hunt Hounds as she closes the portals. Around 9 or 10 hounds in groups of two to four will spawn as the pair work through the room closing the portals. Stay close to Keira, as the white frost is very damaging and Keira can easily be swarmed with hounds if left alone for too long. Once the last of the portals is closed, Keira lowers the shield and nearly faints in Geralt's arms.

Note: You receive 100XP at the completion of this objective

Geralt has two dialogue choices: The way ahead is blocked, but Keira will open the way into the next room.
 * Just don't faint on me - will increase Keira's romance level with Geralt
 * If you can't go on - will not increase Keira's romance level with Geralt

Chase the Wild Hunt
There is a partially blocked side passage ahead which can be cleared with Aard spell, inside are a couple of loot chests and a foglet to defeat. Ahead waits a single Wild Hunt warrior, Nithral.

''Note: You may wish to meditate and prepare potions and oils before jumping down on the platform with the enemy warrior. Once this battle is joined there is no escaping until Nithrail is defeated.''

Fight the Wild Hunt Warrior
Nithral is a rather slow attacker, using a two handed weapon, so attack him quickly and as often as possible before ducking out of the way of his much more damaging swings. At around three-quarters and half Nithrial will summon a rift that brings Hounds to his aid and will attempt to heal inside of a magic bubble, do not attack him directly, instead kill his summoned minions as fast as you can. When all of his minions are gone he will stop healing and again be susceptible to damage, if attacked while healing, Geralt will be dealt a large amount of damage. Nithral heals about 3% every two second while in his magic bubble so be quick about defeating his summoned creatures. Attacks the pierce his armor are most effective.

Note: You will receive 250XP for defeating Nithral

Look for Information
After Nithral is defeated, Geralt will find yet another projection message for Ciri, saying that the place isn't safe and that she should avoid the witches of Crookback Bog. Keira tells Geralt of the legend of the witches, and Geralt realizes if he is to find Ciri's path, he will need to find these powerful witches. Searching this area will find the following clues about the mysterious elven mage:
 * Herbs - Mysterious mage herbalist
 * Empty Potion Bottle - Potion that Keira gave him, must have drank it
 * Half burned notes - Must have burned these notes himself, must have known the Hunt was looking for him
 * After the White Frost - Book of interest to the Hunt

Dispel the Illusion
Geralt notices a wall blocking a doorway that makes his amulet vibrate. Keira gives Geralt a illusion dispersing item called The Eye of Nehaleni which can be used to enter through the doorway and find the exit through the wall of illusion. ''Note: At the end of the chamber where you fight Nithral opposite the side where the elven laboratory is setup is a blocked up doorway which can be cleared with Aard. Inside is an illusion that can be dispersed with The Eye of Nehaleni. Beyond the illusion is a flooded area with loot and a chest with a particularly powerful sword guarded by a foglet.''

Follow Keira
They nearly make it to the surface, when Keira asks Geralt to continue in the opposite direction so she can find the Magic Lamp the elf promised her. Geralt can either choose to leave, or go with her, ending the quest and starting the new quest, Magic Lamp.

Closing Quest Description
"Barely had our heroes entered the underground chambers when they encountered the enemy. The Wild Hunt had reached the spot before them - and they, too, were searching for Ciri. The Hunt had in its ranks a navigator, a powerful mage able to teleport its warriors from place to place in the blink of an eye.  Geralt and Keira, on the other hand, made their way slowly on foot, encountering obstacle after obstacle.  All might have been lost had our heroes not happened across a morphotic projection the elven mage had left for Ciri.  The mage's illusion guided her towards his lair and called her "Zireael" - meaning "swallow" in Elder Speech.  Hearing this, Geralt gained two vital clues: the mage clearly knew Ciri well, and he must have painted the swallows on the walls to direct her.  The road through the underground was not an easy one to travel.  The mage had set a great many traps that Ciri could easily evade but which would trip up any who chased after her. In the end Geralt and Keira eliminated the Wild Hunt's lead and began nipping at its heels. Ciri's pursuers did not find what they were looking for. They departed empty handed, leaving one warrior behind to tend to Geralt and Keira. He proved a weak match for the witcher and the sorceress, but their victory was bittersweet, as in the underground passageways Geralt found neither Ciri nor the elven mage. All he could now do was follow the hints provided by yet another morphotic projection the mage had left behind. Geralt finally learned the truth about Ciri and the witch from the mouth of an illusion. The mage's projection corrected and supplemented the information left behind by Hendrik - Ciri's opponent had not been one ordinary witch but the three Crones, mysterious and powerful beings dwelling in Crookback Bog. Who they truly were and what had happened to Ciri at their swampy home - that, dear reader, you will learn in the pages that follow."

- Dandelion

Trivia

 * There is a ignitable torch in the room where Geralt and Keira fight to close the three frost portals. This can be lit without regard to the portals spewing the White Frost into the cavern, against common sense.