BG3: Investigate The Masons Guild [Selunite Resistance Quest]

Look no further than my Investigate the Masons Guild BG3 guide to learn all about how to complete the quest and its secrets.

The “Investigate the Masons Guild” in BG3 is one of the many quests you can initiate when in the Shadow Cursed Lands. It is a part of the Selunite and Shar Lore, making it a fun questline if you’re into learning all the lore in BG3. Furthermore, it is a vital part of the “Investigate the Selunite Resistance” quest line that you may or may not have triggered in Act 2.

Key Takeaways
  • The “Investigate the Masons Guild” is a Subquest of the Selunite Resistance quest line in BG3.
  • The quest line is only available in Act 2 of BG3.
  • Access to the Last Light Inn Tieflings and protection from the Shadow Curse are essential for the quest.
  • You need to investigate the basement of the Masons Guild using a Tower Shaped Key.
  • There is a Wraith and several shadows guarding the Mason’s Logs.
  • Reading the Mason’s Logs will complete the entire quest chain.

What Is “Investigate The Masons Guild” Quest Line

Masons Guild Quest Guide
Investigate The Masons Guild Quest (Image Credit: eXputer)

Investigate the Masons Guild BG3 is one of the critical subquests of the “Investigate the Selunite Resistance” questline. It is an integral part of the Shar Vs Selunite lore.

Additionally, it is responsible for uncovering many of the secrets of the Shadow-cursed lands in Act 2 of BG3. Furthermore, it is a fun quest, especially if you’re keen on pursuing Shadowheart romantically. 

Start Investigating The Selunite Resistance

To start the “Investigate the Masons Guild” quest in BG3, you must first start the “Investigate the Selunite Resistance” questline as soon as you reach the Shadow-cursed Lands.

  • Simply navigate towards the Abandoned Potter’s Workshop (X: -54, Y: 12).
  • You must obtain a note from the locked chest within and read it to initiate the quest.

How To Investigate The Masons Guild

To complete the “Investigate the Masons Guild” quest, you must return to where you started the main quest, the Abandoned Potter’s House. However, the completion requires more than just the location. You will need the Tower Shaped Key, protection from the Shadow Curse, and land a few perception checks at certain areas. From personal experience, I would suggest dropping down a save each time you enter a new area.

Follow the steps listed below to navigate the Masons Guild:

  1. Fast travel or navigate to the Reithwin Town Waypoint and head North towards the Masons Guild.
    Map to the Masons Guild
    Masons Guild Map Location (Image Captured by eXputer)
  2.  Once at the Masons Guild, head inside and look for the Ornate Wooden Hatch (X:-128, Y:26).
    Masons Guild Hatch Location
    Ornate Wooden Hatch Location (Image by eXputer)
  3. Enter the wooden hatch into the basement and head towards the farthest wall.
  4. Walk around the middle section and try to pass the perception check for the Tower Shaped Keyhole.
    Tower Shaped Keyhole
    Tower-Shaped Keyhole Herald (Image Credit Copyright: eXputer)
  5. Head inside and try to unlock the chest in the left corridor.
    Masons Guild Locked Chest
    Corridor Chest at Masons Guild (Image credit: eXputer)
  6. If you choose to go for the chest, you need to succeed in the lockpick roll. Otherwise, you will trigger a trap that requires you to pass 3 checks in a row or fight 3 Gargoyles.
    Masons Guild Gargoyle Trap
    Gargoyle Trap (Screenshot Captured by eXputer)
  7. In the next room, prepare yourself for battle against a Wraith and several shadows. I did accidentally burn the Mason’s Log using a fireball so be careful with AoE spells.
    Masons Guild Wraith Battle
    Wraiths and Shadows at the Masons Guild (Image by eXputer)
  8. After clearing the room, look for the “Mason’s Log” on the table in the middle of the room.
    Masons Log Guild
    Mason’s Logs (Screenshot Grab: eXputer)
  9. Reading it will complete the quest “Investigate the Mason’s Guild” and the “Investigate the Selunite Resistance” quests.

Requirements For The Quest

Tiefling Mattis
Mattis the Tiefling in BG3 (Image Captured by eXputer)

This section will cover how to obtain some of the requirements listed to complete the quests above. While they are easy to obtain, knowing that you need them is a very vague and cryptic instruction that more than most players miss. 

How To Get The Tower-Shaped Key

  • If you helped the Tieflings escape in Act 1, you might find most of them located at the Last Light Inn.
  • The Tiefling you want to look for is Mattis.
  • Mattis is a Tiefling in Mol’s gang and can be found on the ground floor of the Last Light Inn.
  • You can either buy it from him for 1000 gold or roll a couple of deception/persuasion checks for him to give you the key in exchange for your heroic services.

Protection From The Shadow Curse

The protection from the Shadow Curse is one of the main tricks in Act 2 that you must decide on yourself. There are many ways to do so, but they will vary on the choices you have made so far in BG3. Personally, I prefer using the Dancing Lights spell until I get to the Last Light Inn so I can get Isobel to bless my party.

You can get protection from the Shadow Curse through these effects:

  • Obtain a Pixie’s blessing.
  • Use one of the many Moonlanterns you’ll come across.
  • Obtain Selune’s blessing via Isobel.
  • Use a torch to remain permanently in the light.

My Thoughts

Completed Masons Guild Questline
Completed Quest Line (Image By eXputer)

BG3 is a game full of lore, and it is one of the best things about it. Naturally, I love discovering all the secrets, especially in the Underdark/Shadow-Cursed Lands. The “Investigate the Masons Guild” BG3 quest also makes its fair share of contribution to not only your riches but also the attitude your companions have towards you. A word of advice: pick up the Masons Logs for more Selunite Resistance quests later in BG3.

Finally, the time has come to conclude the guide on how to Investigate the Masons Guild in Bg3. While you are here, feel free to check out some other Bg3 guides like the Best Paladin Oaths. If that isn’t your style, you can always learn more about how to complete the Dank Crypt Dungeon.

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Sameer is a Senior Writer & Editor for all sorts of guides on eXputer. He has dove deep into many gaming genres and ended up investing 8,000+ hours on COD titles, Pokemon games, Witcher 3, Minecraft, and Bloodborne. Sameer has a degree in Writing and Editing from the University of Michigan. Additionally, he has several years of writing experience and has worked for Mashable previously. Get familiar with Sameer's gaming library on his PSN and Steam profiles.

Experience: 5+ Years || Previously Worked for Mashable || Education: ACCA

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