The Deep North introduces two important dungeon types that are central to progression: Winding Tunnels and Mörkhalla. They serve very different purposes, but you will need to explore both if you want to complete the biome and eventually reach Kall Fimbulbringer.
Winding Tunnels are the earlier and much larger dungeon type. They are your main source of Frost Cores, weapon and armor Moulds, and Moulds for the Intricate Key. Mörkhalla comes later and is much shorter, but also much more dangerous. It contains valuable endgame loot and the Malicious Ice required to trigger the Jotun Invasions that lead toward the final boss.
In this guide, we will cover where to find both dungeons, the enemies you can expect inside, the most important loot to look for, and how each dungeon fits into your overall Deep North progression.
If you are looking for the complete progression route from entering the Deep North all the way to the Aesir Passage, refer to our Deep North Progression Guide.
The Winding Tunnels
The Winding Tunnels are the first major dungeon you should explore in the Deep North. They are large, maze-like underground areas and are one of the most important sources of Frost Cores, Moulds, and the Intricate Key Moulds needed for later progression.
Where to Find Winding Tunnels
Winding Tunnels are found underneath Abandoned Villages in the Deep North.
When you find one of these settlements, search the largest longhouse or multi-story building. The entrance is usually hidden inside as a large opening leading underground. The tunnel itself does not receive a map marker automatically, so make sure to mark the village once you find one.
How to Enter
You do not need a key or any special progression item to enter a Winding Tunnel.
Simply locate the opening inside the abandoned building and drop down into the dungeon. It is worth making sure you are properly prepared before going in, because the tunnels can contain 30 or more rooms and are much larger than most earlier Valheim dungeons.
Bring strong Deep North food, healing, enough inventory space, and a reliable light source.
Enemies Inside Winding Tunnels
The main threat is the Eyeless One.
Eyeless Ones can hide underground and suddenly burst out when you get close, dealing heavy damage in the process. They are also one of the better sources of Mould drops, so they are worth killing rather than simply running past.
You will also encounter Elakings, smaller enemies that can emerge from Wardrobe Shafts throughout the dungeon. These shafts act as spawners, so leaving one active can result in more enemies appearing while you are exploring nearby rooms.
Finally, you can find Luminous Larvae attached to the tunnel walls. These are passive and can simply be collected. Picking one up also unlocks the Hooded Lantern, which is particularly useful for exploring the dark tunnels.
Important Loot
The main reason to explore Winding Tunnels is the loot.
Frost Cores are one of your biggest priorities. You need 20 in total to build both the Frigid Kiln and Frost Foundry, so you will usually need to clear several tunnels before completing your crafting setup.
You can also find a large variety of weapon and armor Moulds. These are used together with Bloodgold and the Frost Foundry to craft Deep North equipment.
Most importantly, Winding Tunnels can provide the Mould: Intricate Key, which is required to create the keys used to enter Mörkhalla later in the biome.
Other useful loot includes:
Timberwood
Scrap Iron
Silver Necklaces
Long Claws
Luminous Larvae
and additional crafting materials scattered throughout the dungeon.
Do not only search chests. Important loot can come from rubble piles, Wardrobe Shafts, roots, enemies, and other breakable objects, so clearing rooms properly is much more rewarding than simply running toward the end.
How to Navigate the Tunnels
Winding Tunnels can become confusing very quickly.
A good trick is to place lanterns or other markers facing back toward the exit as you move deeper into the dungeon. This makes it much easier to find your way back once your inventory is full.
Clear side rooms as you encounter them, destroy rubble, and check every Wardrobe Shaft before moving on. Since loot is distributed throughout the dungeon, skipping half the rooms can mean missing important Moulds or Frost Cores.
Once you have fully cleared a tunnel, mark it as completed on your map so you do not accidentally return to the same one later.
Why Winding Tunnels Matter
You will need to clear Winding Tunnels several times during normal Deep North progression.
They provide the Frost Cores needed for your crafting stations, the Moulds used to craft Nord equipment, and the Intricate Key Moulds required to enter Mörkhalla.
Once you have your Frost Foundry running and enough Intricate Keys prepared, the next major dungeon becomes Mörkhalla.
Mörkhalla
Mörkhalla is the second major dungeon type in the Deep North and comes later in the biome's progression. Compared to the Winding Tunnels, it is much smaller, usually containing only a handful of rooms, but the enemies are more dangerous and the dungeon is directly tied to unlocking the path toward Kall Fimbulbringer.
Where to Find Mörkhalla
Mörkhalla appears as a large, dark stone tower in the Deep North and is much easier to recognize from a distance than a Winding Tunnel.
The structures generate throughout the biome at higher elevations, so exploring inland and marking each tower you find is worthwhile.
How to Enter
Unlike Winding Tunnels, you cannot simply walk into Mörkhalla.
The main entrance is elevated above ground level, so you will usually need the Grappling Hook to reach it. Once inside, descend through the upper structure until you reach the chained door.
Opening this door requires an Intricate Key, and the key is consumed when used. This means every Mörkhalla you enter normally requires another key.
If you still need Intricate Keys, our Deep North Progression Guide covers how to obtain the Mould, Bloodgold, Liquid Frost, and the finished key.
Enemies Inside Mörkhalla
Mörkhalla is primarily defended by Jotun enemies.
Krigen are the main melee threat. They have a large Health pool and can deal heavy damage, so avoid fighting several at once if possible.
Hexen provide magical pressure and are particularly dangerous when they are supporting other enemies.
You can also encounter Shapeless Pulp, along with imprisoned creatures such as Dvergr and Fulings in some rooms.
Because the dungeon is compact, enemies can pile up quickly. Clearing rooms methodically is usually safer than rushing directly toward the bottom.
Important Loot
Mörkhalla contains some of the most valuable dungeon loot in the Deep North.
Ancient Chests and Jotun's Chests can contain Moulds, Timberwood, Scrap Iron, Bloodgold-related materials, gemstones, and other useful resources. Ancient Chests are also the source of Ancient Coins.
You should also look for Memorial Coal in coal piles and firepits throughout the dungeon. Memorial Coal is used later at North Memorial Places for additional weapon progression and access to Deep North weapon Essences.
Do not rush straight to the objective and leave. Mörkhalla is short enough that it is worth checking every room and chest before finishing the dungeon.
Navigate Carefully
Mörkhalla is much shorter than a Winding Tunnel, but the layout is more vertical.
The dungeon contains stairs, elevated sections, narrow platforms, and large drops. Keep your Grappling Hook available while moving through it, since it can help with traversal as well as recovering from awkward positions.
Because there are only around 4 to 5 rooms per dungeon, navigation itself is generally much simpler than in the Winding Tunnels.
Destroy the Malicious Ice
The main progression objective is found in the end room.
Here you will find Malicious Ice. Destroying it does not give you a normal resource drop. Instead, it triggers The Jotun Advance and starts a Jotun Invasion somewhere in the world.
Completing that invasion rewards Malicious Blood, which is required to eventually open the Aesir Passage.
You need three Malicious Blood, so normal progression requires you to clear three separate Mörkhalla dungeons and trigger three invasions.
Why Mörkhalla Matters
Winding Tunnels primarily establish your Deep North crafting progression. Mörkhalla pushes you into the final stage of the biome.
The basic progression is:
Craft an Intricate Key → Enter Mörkhalla → Loot the dungeon → Destroy Malicious Ice → Complete the Jotun Invasion → Obtain Malicious Blood
Repeat this three times and you will have the Malicious Blood required for the Aesir Passage.
For the full progression from Mörkhalla through the invasions and into the final boss, refer to our Deep North Progression Guide.
