Follow the Mausoleum route to the Source
Use the concealed passage beside the altar to the right of the Mausoleum entrance and activate its torch, then solve the flame puzzles inside. Collect the three High Clerics' Golden Keys and use them to open the skull-shaped Source Gate.
Enter the Mausoleum from the cemetery
- Travel south from Underkeep Village to reach the cemetery and the Mausoleum entrance.
- Find the concealed approach beside the altar to the right of the Mausoleum entrance to locate the hidden passage.
- Activate the torch inside the hidden passage to follow the concealed approach into the Mausoleum.
The cemetery also has four riddle altars outside the Mausoleum, with puzzles that use objects found around the graves. The concealed approach provides an alternative entrance route. If your immediate aim is to continue into the Mausoleum, follow the passage directions above.
Solve the flame and brazier puzzles
- Use the blue flame in the three-color puzzle to solve that obstacle.
- Pass through the warned corridor without touching its flames to follow the instruction for that section.
- Light only the entrance brazier and the four braziers arranged in a square before the Chambers of Endless Sleep door to complete its brazier pattern.
Keep the flame instructions tied to the puzzle you are facing. The blue flame is the answer to the color puzzle, while the warned corridor calls for leaving its flames untouched. At the Chambers of Endless Sleep door, check the entrance brazier as well as the square arrangement.
Find every Golden Key before returning to the gate
The required Golden Keys come from the High Clerics in the Mausoleum branches. Ordinary cemetery graves and the optional Skeleton King do not provide these keys. Use the table as a checklist of key holders, rather than a required order for fighting them.
| High Cleric | Required item | Where to use it |
|---|---|---|
| Maltherion the Sleepless Watcher | Golden Key | Source Gate |
| Thalric the Undying Flame | Golden Key | Source Gate |
| Zerethic the Heart Eater | Golden Key | Source Gate |
- Defeat each listed High Cleric to obtain the three Golden Keys required for the Source Gate.
- Return to the skull-shaped Source Gate after collecting every required key, bringing the branch objectives back to the gate.
- Use the Golden Keys to clear the Source Gate's three locks and open the route into the chamber.
Choose whether to end the Source
After opening the Source Gate, defeat the guardians in the chamber to reach the Source's choice. Select 'End it' to destroy the Source and complete the Heart of the Source objective. Select 'Let it live' to spare the Source, which leaves that quest marked as failed.