Valheim: How to Farm Thunderblood and Frostfire Essence for Nord Weapons

Thunderblood Essence and Frostfire Essence are the two materials that separate a plain Nord weapon from an elemental one in Valheim 1.0. Neither drops from normal Deep North wildlife. Both come from a single repeatable encounter: an Ancient Altar, a stack of Memorial Coal, and an undead Fallen Warrior that has to be killed for its glowing orb.

Quick answer: Feed three Memorial Coal into an Ancient Altar on the Deep North surface to summon a Fallen Warrior. Each one killed drops either a Thunderblood or a Frostfire Essence at random.

Where to get Memorial Coal in the Deep North

Memorial Coal is the fuel for the whole loop, and it only comes from underground. Pits and cave mouths across the Deep North lead into the Winding Tunnels, and the most reliable way to collect coal there is to smash the braziers scattered through the passages.

Because each summon costs three Memorial Coal, a single tunnel run rarely supports more than a handful of fights. Clear the braziers you pass rather than rushing for the exit, and bank the coal at your base between trips.

Memorial Coal is not furnace fuel. Burning it in a kiln or smelter destroys the only resource that can trigger an Ancient Altar.

How the Ancient Altar summon works

Ancient Altars sit on the Deep North surface, usually paired with a runestone. There is no fixed spawn point for them, and a single Deep North region can hold more than one, so finding your first altar is a matter of exploration. Once you have one, it becomes a permanent farm.

Inserting coal prints the line “The Ancestors heed your call” and spawns a Fallen Warrior in the ring around the altar. You can insert several charges back to back, and the altar answers each one, so multiple warriors will come at you simultaneously if you keep feeding it.

How the Ancient Altar works — The Ancient Altar confirms the summon with an on-screen message once Memorial Coal is consumed. Shown at 00:27 in Jade PG’s video. Image: Iron Gate AB

Property	Fallen Warrior
Health	750
Resists	Burn, slash, pierce, fire
Immune	Poison
Weak to	Spirit damage
Drop	1 Thunderblood or Frostfire Essence (random)
Cost per summon	3 Memorial Coal

Which essence you get is not something you can steer. The drop is rolled per kill, so a run that produces mostly Frostfire is normal, and the fix is simply more kills.

Build a pit arena around the altar

Fighting at an open altar means wandering Deep North enemies join the fight. Walling the altar into a sunken arena solves both problems at once: warriors cannot leave, and nothing outside can walk in.

Clear the terrain first. Use the Snow Shovel to strip the deep snow away from the altar and the nearby runestone so you have flat, buildable ground to work with.

Switch to the Hoe and use Raise Ground to build a tall earthen wall in a full circle around the summoning ring. Keep raising until the wall is high enough that a warrior inside cannot climb out and a Jötunn outside cannot step over.

Raising earth walls with the Hoe — Raise Ground on the Hoe stacks the earthen barrier that turns the altar into a sealed pit. Shown at 01:36 in Jade PG’s video. Image: Iron Gate AB

Place Ballistas along the top ridge of the wall, facing outward. They handle the roaming threats that gather during long farm sessions, including Häxan and trolls, while you stay focused on the pit.

Add a small enclosed chamber just outside the ring with a workbench and a portal. The workbench lets you repair between waves, and the portal turns a full inventory of essence into an instant trip home.

Insert your coal and drop into the pit. Kill the warrior, collect the essence orb, and repeat. Every additional charge you feed the altar before jumping in raises the difficulty and the yield in the same motion.

Fighting summoned warriors in the pit — Frostfire and Thunderblood Essence left on the arena floor after a cleared wave. Shown at 04:44 in Jade PG’s video. Image: Iron Gate AB

Fighting Fallen Warriors efficiently

The resistance profile is the whole fight. Slash, pierce, fire and burn all land softly, poison does nothing at all, and spirit damage does the heavy lifting. A Silver Sword carries spirit damage and remains a strong pick against these enemies despite being far below the Deep North tier on paper, and Frostner is worth keeping in the rotation for the same reason.

Comparing weapons against fallen warriors — The Silver Sword's spirit damage line is the number that matters against Fallen Warriors. Shown at 06:09 in Jade PG’s video. Image: Iron Gate AB

Warriors shrug off knockback, so pushing them away is not a reliable escape.
Parrying works well and opens a clean stagger window for a heavy follow-up.
At point-blank range you can occasionally phase through a warrior, which throws off spacing.
Standing on the raised wall edge lets you strike downward into the pit while staying out of melee reach.
A two-handed sledge lands area damage through structures, which helps when several warriors bunch up.

Combat tactics and multi-summoning — Melee trade beside the lit altar, where stagger timing decides how fast the wave ends. Shown at 05:31 in Jade PG’s video. Image: Iron Gate AB

Stack summons only once the walls are finished. A large batch of warriors dropping essence orbs at the same time is the fastest version of this farm, but it is also the version that kills you fastest if anything can flank you.

Mass spawn drop test — Stacked summons in the sealed pit produce a floor covered in essence orbs. Shown at 09:26 in Jade PG’s video. Image: Iron Gate AB

Turning essence into Thunderblood and Frostfire weapons

Essence upgrades a completed Nord weapon rather than crafting one from nothing. First obtain the matching Mould and the Nord weapon itself, then use Bloodgold plus the recipe’s materials at the Black Forge to create the cast. Finish the cast in a Frost Foundry. Produce Bloodgold by smelting Petrified Tissue in a Blast Furnace.

Once the Nord weapon exists, every elemental conversion uses the same shape of recipe at the Black Forge: 20 Bloodgold, the Nord weapon, and 1 essence. That holds for all twelve weapon types, from the Sword and Greatsword through to the Bow and Crossbow. The two magic casts are the exception and are made at a level 3 Galdr Table.

Recipe	Station	Materials
Any Thunderblood weapon	Black Forge	20 Bloodgold, 1 Nord weapon, 1 Thunderblood Essence
Any Frostfire weapon	Black Forge	20 Bloodgold, 1 Nord weapon, 1 Frostfire Essence
Cast: Lightning Strike	Galdr Table	10 Bloodgold, 5 Nornathread, 1 Thunderblood Essence, 1 Mould
Cast: Echo Spike	Galdr Table	10 Bloodgold, 4 Nornathread, 1 Frostfire Essence, 1 Mould

Which element to spend an essence on depends on the damage split, not the total. Using the sword line as the reference point, Thunderblood keeps physical damage high and bolts lightning on top, while Frostfire trades slash away for a large frost component and a small fire one.

Weapon	Listed base damage
Nord Sword	170 slash
Thunderblood Sword	180 slash + 45 lightning
Frostfire Sword	138 slash + 88 frost + 12 fire

Adding those components together is misleading. Enemy resistances apply to each damage type separately, and Barka resist both frost and lightning while taking extra damage from fire. A weapon whose numbers look larger on the tooltip can land for less against the specific thing you are fighting.

How to confirm the farm is working

Three checkpoints tell you the loop is running correctly. The altar accepts the coal and prints the ancestor line, which confirms the summon fired rather than the coal being wasted. The warrior leaves a glowing essence orb on death, which is the only way either essence enters your inventory. And back at the Black Forge, the elemental variant appears as a craftable entry the moment you are holding the Nord weapon, 20 Bloodgold and the matching essence.

If the Black Forge does not list the conversion, the missing piece is almost always the weapon itself rather than the essence. A cast is not a finished weapon, and it cannot be upgraded until it has been hardened in the Frost Foundry. Get one Nord weapon fully finished, convert that first, and let the rest of the arsenal wait for later coal runs.