Investigating the Mines is a quest in Divinity: Original Sin and Divinity: Original Sin - Enhanced Edition. The quest is obtained by speaking to Icara at the Homestead after freeing her in Eternal Winter. It is important to explore and loot everything you can from the mines as it will become inaccessible at the end of this quest. The Death Knights encountered withing the mines are all invulnerable and you will have to sneak or use invisibility potions to get past them.
As all invulnerable Death Knights in the game can be avoided, completing this quest is optional.
- Head out of the Eastern exit in Silverglen (by Lawrence's office) and keep to the East. You will eventually come across a goblin guarding a bridge, beyond which is the entrance to the Troll King's Cave. It is a linear path from here, so continue past the cave entrance and kill all the goblins you encounter to reach the mines.
- You will hear a voice calling out to you when you enter the mines. Move some boxes to the north to reveal Mikas and speak to him to trigger Hide-And-Mikas and Rogue Dread Lords. Resolve Hide-And-Mikas through conversation to continue.
- Walk southeast past some skeleton miners to trigger Miner Control. This quest will need to be resolved to progress further. Along the way is a Tenebrium vein that can be used for The Troll's Bounty. With high enough perception you may locate a dig spot northwest of the idol room.
- Speak to Dreksis to update Goblin Trouble.
- Enter the guard room to initiate A Long Fuse.
- With careful timing or through the usage of Invisibility spells or potions walk past the patrolling Death Knight. Hug the west wall and you will come across a path that ends in a pile of Immaculate bodies for some loot and ore (2730 Exploration XP). Teleport down to the crates for more loot.
- Continue past another Death Knight with the same avoidance methods to the southeast past the bridge then head north to trigger a Waypoint Portal (3150 Exploration XP). Further North is another Tenebrium vein.
- Gather your party members if you left any behind and send them to the Waypoint Portal at the entrance of the mine. At this point consider returning to Silverglen to turn in The Troll's Bounty for Rot1 non-leathal Void Damage per Turn Immunity. Rift travel doesn't work in the mines so it might be a good idea to unload all your loot. When ready, teleport to the Luculla Mines - Chasm Waypoint Portal to reunite your party.
- Using the same avoidance methods move southwest past the trap field all the way to the barricade. You can avoid the traps by walking on the tracks if your perception is not high enough.
- Walk past the barricade and win the Charisma game (5460 Charisma XP). Alternatively, you can kill the Immaculates for 22100 XP or even do both.
- Head south and then east, using Rain and AoE spells to deal with the fire and traps. Break the wall and sneak your way directly east to a Temple Door (2730 Exploration XP).
- Interact with the door and speak the password you received from the Miner Control quest, Sadakandras, to open it (2730 XP).
- After you have looted everything, head up the stairs to watch a cutscene with Leandra and resolve the Rogue Dread Lords quest.
- Note: You can teleport past the stairs and thus delay the cutscene for until you've had time to loot everything and clear a path.
- The Death Knights are invulnerable but extremely slow. Even if you didn't teleport past the stairs, you should still have plenty of time to loot everything even during battle mode. Head for and use the mirror to the Northeast to teleport to the Library and loot everything there. The Death Knights will not follow.
- Note: Only one party member needs to reach the mirror; once any character interacts with the mirror, the whole party is teleported with them. A character with the Battering Ram skill can quickly get through the rubble blocking the way through the archway.
- Use the next mirror to enter the High Priest's Office. Loot everything then head east through the forcefield (2730 Exploration XP). Loot everything here including Leandra's Spell to update the quest.
- Return to the mirror and use it to teleport to the crypt. Do not dig any of the dig spots yet. On the railing across there is a switch which deactivates the lava traps on the three dig spots, which hold skill books. The dig spot to the south of the mirror contains a Magic Unlock Scroll.
- Use the mirror to teleport to the Entrance Hall.
- You will see a chest when you head south but you need to be quick to open it or pick it up before it gets destroyed.
- Continue south along the linear path until you reach the final mirror. Teleport to 'The Sun Outside' to leave the dungeon and resolve this quest (9100 XP).