Sunken Crypts

0:01 Sunken Crypts are stone crypt dungeons of the Swamp in Valheim, sealed behind iron gates that open only for a player carrying the Swamp Key dropped by The Elder. Inside, halls lit by green flames lead to rooms walled off by muddy scrap, and mining it is how the game hands out its first iron. The crypts also hold the Withered Bones needed to summon Bonemass and, in some, the Vegvisir that reveals his altar.

Quick facts

How to find Sunken Crypts

0:13 A crypt is a squat stone mausoleum whose two green-flamed torches can be spotted from a distance. Crypts generate in clusters of four, and only deep inside a Swamp, so one usually means others nearby (Sunken Crypts, Valheim Wiki). A Draugr and an Oozer may lurk by the door. The flat roof is out of reach of Swamp creatures, and Kysen builds a portal there so a death inside does not mean a long walk back.

The Swamp Key

0:48 The Swamp Key is the Elder's reward, and one key opens every crypt in the world; it is not used up. It only has to be in the inventory the first time a gate is opened, after which that crypt stays open (Swamp Key, Valheim Wiki). The lock enforces the boss order between the Black Forest and the Swamp.

Inside a Sunken Crypt

0:12 Every crypt opens onto a central hall with wings to either side and ahead, and each wing branches into more rooms; the wiki's location data gives a crypt 20 to 30 rooms (Point of interest, Valheim Wiki). Jecca Games clears one wing at a time, taking only right turns so that no room is missed. Some doorways are closed by unlocked iron gates, which can simply be opened; smashing them wastes durability and yields nothing.

1:05 The walls of scrap blocking many doorways are Muddy Scrap Piles, and mining them is the crypt's purpose. Any pickaxe, even the antler one, breaks them. A pile has 30 segments, and each has a 14.29 percent chance of yielding one Scrap Iron, about four per pile, plus smaller chances of Leather Scraps and Withered Bones (Muddy Scrap Pile, Valheim Wiki). Leftover slivers hide in the rubble, and pieces clipping through a wall can drop outside the crypt.

Enemies in Sunken Crypts

Values from the Valheim Wiki; see Draugr and Swamp Creatures.

2:09 The crypt dwellers are Draugr with axes (48 slash) or bows, the rarer purple-eyed Draugr Elite with a sword, and Blobs whose poison cloud does 90 damage within four meters. Draugr sometimes spawn inside a scrap pile and strike from within it. Killed enemies do not return.

1:41 Body Piles, heaps of corpses announced by the buzz of flies, are draugr spawners: while a player is within 20 meters they raise a new draugr every six seconds until two stand nearby, 14 percent of them Draugr Elites (Body Pile, Valheim Wiki). Kysen wounds the first two draugr without killing them, so the pile stops spawning, then destroys it from range or with the Stagbreaker. Left behind a scrap pile with a gap to shoot through, a pile becomes a farm for the Draugr Elite Trophy the Iron Sledge needs (Weapons and Shields).

Sunken Crypt loot

8:22 Crypts hold a few stone chests, which Samo rates the best source of iron in the swamp; he empties them and leaves many of the slower scrap piles standing. About one roll in five is a stack of scrap iron. A chest rolls two or three of the following, never the same item twice (Loot chest, Valheim Wiki):

2:36 The floors add Yellow Mushrooms, amber, Entrails and Ooze. Withered Bones come from scrap piles and chests, and ten of them summon Bonemass at his glowing skull altar. Some crypts contain the Vegvisir that marks the altar on the map (Runestones and Vegvisirs).

How to clear a Sunken Crypt safely

1:16 Kysen brings bronze armor, a mace and buckler, a bow with fire arrows, the Stagbreaker, poison resistance mead, and two health foods with one stamina food. The raised ledge inside the entrance keeps melee draugr off, though archers can still shoot and Blobs hop up. A campfire on the ledge restores the Rested bonus and dries off the Wet effect; the crypts count as sheltered, so the player stays dry unless forced to swim a flooded corridor (Weather, Cold and Wet; Mead and Potions).

Kysen and Samo mine only part of a scrap pile, look through the gap and kill whatever waits beyond with arrows or the Stagbreaker, whose area blow passes through scrap without breaking it. Blunt weapons suit Blobs, and a bronze buckler can parry the Draugr Elite. A stray swing can break the green wall torches for good.

Getting the iron home

1:44 Scrap Iron weighs 10 a piece and, like all metal, cannot pass through a portal unless a world modifier allows it (Scrap Iron, Valheim Wiki). Jecca Games drops each load on the entrance platform and collects it on the way out, then ships it; a Karve carries four stacks and a Longship eighteen, so they forge the Longship's iron nails first (Sailing and Ships; Metals and Smelting). After Bonemass, his Wishbone reveals rarer scrap piles buried in the open swamp.

History and 1.0

Iron Gate rebuilt the crypts during the closed beta; its development news of October 2020 said "we pretty much remade our sunken crypts from scratch" (Development news and new content, Iron Gate). Patch 0.148.6 of March 2021 fixed tombstones getting stuck at the entrance (0.148.6, Iron Gate). The Valheim 1.0 Release left the crypts' layout alone but improved the Blobs' jump animation and put Iron Battle and Protection Idols, used at the Forge of Potential, among the chest loot of Swamp ruins, graves and Sunken Crypts (Valheim 1.0 Has Arrived!, Iron Gate; Game8).

Frequently asked questions

Is the Swamp Key used up? No. One key opens every crypt, and a crypt stays open once unlocked.

Do Sunken Crypts respawn? No. Enemies killed inside stay dead and scrap piles and chests do not refill; only Yellow Mushrooms regrow, and intact Body Piles keep spawning.

How much iron is in a Sunken Crypt? It depends on the layout: each muddy scrap pile averages about four scrap iron and a chest stack holds 10 to 20, so the total follows the number of piles and chests.

Sources

• Sunken Crypts, Swamp Key, Muddy Scrap Pile and Scrap Iron, Valheim Wiki (weirdgloop)
• Draugr, Draugr Elite, Blob, Body Pile and Oozer, Valheim Wiki
• Loot chest and Point of interest, Valheim Wiki
• Development news and new content, Iron Gate Studio, Oct 30, 2020
• 0.148.6, Iron Gate Studio, Mar 23, 2021
• Valheim 1.0 Has Arrived!, Iron Gate Studio, Sep 9, 2026
• List of All Idols, Game8
• Complete IRON Mining & Crypt Guide, Jecca Games (video)
• Best Way to Deal with Sunken Crypts, NubbQueen (video)
• Valheim Swamp Crypt - EASY GUIDE!, Kysen (video)
• 30+ Need to Know Valheim Tips for the Swamp!, Samo (video)