Source of Corruption is the next main story quest in the Fangs of Asterkarn expansion for Grim Dawn, and it becomes available the moment you close out the Bloodbound story beat in Kurnhold. It sits several quests deep into the new western region, so you need to have worked through the earlier Kurn chain before it appears in your log.
Quick answer: Finish Bloody Sins by defeating Yurra Voideye at Guardian’s Sorrow, then return to Kurnhold and speak with High Chieftain Yigra. Source of Corruption unlocks automatically once that conversation ends, alongside your +250 Kurn Reputation and Bloodbound Totem reward.
How to unlock Source of Corruption
The quest is not something you go looking for on the map. It is handed to you as the direct continuation of the Bloody Sins conclusion, so the only requirement is finishing the quest that comes right before it.
The Fangs of Asterkarn quest chain leading here
Source of Corruption arrives near the middle of the expansion’s story arc. If it has not shown up yet, one of the earlier quests below is still open. The chain runs in a fixed order through the Frostveil Highlands and into Kurnhold.
| Order | Quest | Key outcome |
|---|---|---|
| 1 | Trouble in Asterkarn | Opening quest that leads into the new region |
| 2 | The Asterkarn Incident | Defeat Garmir the Lost, rescue the scouts, meet Ulfgarn; rewards Frozen Aster and +100 Kurn Reputation |
| 3 | Journey to Kurnhold | Travel west to reach the Kurn settlement |
| 4 | Bloody Sins | Defeat Yurra Voideye at Guardian’s Sorrow; rewards Bloodbound Totem and +250 Kurn Reputation |
| 5 | Source of Corruption | Unlocks after speaking with High Chieftain Yigra in Kurnhold |
The Bloodbound and the Great Annihilator
The reason Source of Corruption exists ties back to what Yigra reveals at the end of Bloody Sins. The Bloodbound are not a random threat. They are servants of the Great Annihilator, and the corruption spreading across the Kurn lands traces back to that power. This is the same taint you are sent to purge across the snowy peaks, frozen caverns, and forest valleys of the Asterkarn region.
Note: The land around Kurnhold is broad and full of optional detours, but the main quests advance on a set order, so completing each one in turn is what pushes the story forward to Source of Corruption.
What you need to play Fangs of Asterkarn
Fangs of Asterkarn is the expansion that adds the Kurn storyline, the Frostveil Highlands, and Kurnhold to the game. It requires both the Forgotten Gods and Ashes of Malmouth DLCs to play, so all three need to be installed before this quest chain can appear. The expansion also grows the total game world by roughly 32 percent, which is why the region around these quests is so large to explore.
Once Yigra finishes explaining the Bloodbound threat, you are cleared to start Source of Corruption and continue tracing the corruption to its origin. Keep working through the Kurn faction quests in order and the campaign will carry you straight into it.
