Baldur’s Gate 3: Investigate the Selunite Resistance in Last Light Inn & Mason’s Guild in BG3

Find the secret alter in the Last Light Inn and then investigate the Mason’s Guild secret passage in Baldur’s Gate 3.

Investigate Selunite Resistance Mason's Guild Last Light Inn

Screenshot by Gamepur

Baldur’s Gate 3 portrays a divine conflict between followers of Shar and Selune, echoing a clash between light and shadows. Investigate the Selunite Resistance is a Baldur’s Gate 3 sidequest that drives players to find what remains of the Selunite worshippers in a place as dark as the Shadow Cursed Lands. To complete this side quest, players must first find a secret altar in the Last Light Inn and then investigate the Mason’s Guild secret passage.

How to Investigate the Selunite Resistance in the Last Light Inn in Baldur’s Gate 3

BG3 Selunite Resistance Last Light Inn
Screenshot by Gamepur

Northwest to the Last Light Inn lies a broken rock bridge, a sign posted near the warning you to turn back. This area is plagued with a heavy shadow curse, which means torches and Isobel’s Blessing of Selune won’t be enough.

If the Moonlantern or the Filigreed Feywild Bell hasn’t been acquired yet, it’s better to ungroup the party and use the most mobile character to traverse this first area.

Screenshot by Gamepur

To find the Selunite Resistance altar in the Last Light Inn, enter the house and look for the hole in the floor to the door’s left. Use the Knotted Roots to descend.

Inside this area, a bunch of Meenlock enemies awaits. It’s better to ambush them than to get caught by surprise, so prepare accordingly. Once defeated, head to the back of the room to find the Last Light Inn’s Selunite resistance altar. Read the book on the altar to complete this objective.

How to Investigate the Selunite Resistance in the Mason’s Guild in Baldur’s Gate 3

Mason's Guild Wooden Hatch BG3
Screenshot by Gamepur

The Mason’s Guild is a seemingly empty and small building south of the Last Light Inn. By passing a perception check, an Ornate Wooden Hatch on the floor can be unveiled. 

Related: Baldur’s Gate 3: What are Passive Skill Checks in BG3?

Use this hatch to enter the secret room in the Mason’s Guild. A note reveals that our “thieving journey ends here,” warning us of danger.  

The Gilded Chest up ahead marks the initial challenge this area presents. And boy, is it effective. Upon interacting with the Gilded Chest, two walls will rise and trap the character while fire-spitting gargoyles on the sideburn them to death. Don’t even bother lockpicking it either; it’s completely empty.

Mason's Guild Traps BG3
Screenshot by Gamepur

Head to the next room to pick a fight with several undead and wraiths. After they have been put down, read Mason’s Log on the table to find out that he was, in fact, the leader of the resistance. You’re free to loot the entire place and continue your quest to kill Ketheric and all the other Thorms.