BG3 Mirror of Loss Guide – Full Walkthrough and Hidden Mechanics

by JFFK · February 24, 2026

Welcome to the Mirror of Loss Guide for BG3. We will show you everything you need to know about the Mirror of Loss and its hidden mechanics.

The Mirror of Loss allows you to get up to 3 extra Ability Points on your character, and is vital for fully optimising builds.

Important: This guide inevitably contains some spoilers for Act III and Shadowheart’s story, although I have done my best to minimise them as much as possible.

Table of Contents:

How to Access the Mirror of Loss in BG3

The Mirror of Loss is found in the Cloister of the Sombre Embrace in Act III.

To reach it, you must get past the Shar cultists who are based there, either by making a deal with them or defeating them.
Before going any further, read the Hastily Written Note in the cave behind the breakable wall. This will bypass one of the skill checks required to use the mirror.
Head into the back room of the Cloister of the Sombre Embrace. As you go down the stairs, you enter a wide, open area.
Before reaching the mirror, you will find two NPCs bound there. These are important for Shadowheart’s story.
- Unless you are 100% decided on Shadowheart fully aligning with Shar, you should not interact with these NPCs until you’ve finished with the mirror.
Interact with the huge mirror at the back of the room to begin.

How the Mirror of Loss Works in BG3

BG3 Mirror of Loss Dialogue

The Mirror of Loss involves some hidden dice rolls that make it difficult to understand what’s going on, and this is made worse because the outcomes of your choices are quite ambiguous and poorly explained.

This is how the Mirror of Loss works:

Each character can surrender up to 6 memories to the mirror. After each attempt, you’ll need to interact with the mirror again to make another.
Every time you surrender a memory, a hidden roll occurs, landing on a number between 0 and 4.
Passing a DC25 Religion check to offer a prayer to the mirror gives you a +3 modifier on all rolls at the mirror.
If you get a 0-3, you just see a memory and receive a debuff that lasts until your next Long Rest (can be removed earlier with Remove Curse).
If you get a 4, you see a memory about Gortash and Stelmane, and you will receive a permanent +1 bonus to your Charisma.
If you get a 5 or above, you can choose one of your abilities to receive a permanent +2 bonus to.
- You can get both of these bonuses on your character at the same time, including a total of +3 to Charisma.
- This is impossible to get without passing the Religion check mentioned above.

BG3 Mirror of Loss Ability buff

With this rather complicated set of rules, you have two strategies for the mirror.

Low Risk Strategy

The low-risk strategy is to take the DC25 Religion test straight away. The +3 buff from passing the religion test makes you less likely to get the +1 Charisma boost.

This strategy makes it very likely that you will get the +2 bonus to an ability of your choice, but there’s a fairly good chance you’ll miss out on the +1 Charisma buff.

High Risk Strategy

To maximise your chance of getting both of the rewards, sacrifice 3-4 of your memories before praying to the mirror. This gives you a reasonable chance of getting the +1 Charisma boost, but it’s still far from guaranteed.

Next, pass the Religion check, and then sacrifice the remaining 2-3 memories to get the +2 boost.

This strategy gives you the highest chance of getting both rewards, but also has a markedly higher chance of only getting the +1 Charisma, or getting nothing at all.

For most builds, the low-risk strategy is sufficient because +2 to an ability of your choice is all you need. You only need to take the high-risk option if you’re playing as a Charisma-based spellcaster and want to push your Charisma score to 24.

Important: remember that you can go through this process for each character in your party individually, not just once per party!

How to Pass the Religion Check

BG3 Mirror of Loss Religion Check

Arguably, the greatest difficulty with the Mirror of Loss is passing the DC25 Religion check, which is required to access the +2 ability score boost.

If you are playing on story, normal or tactician difficulty, you can save scum (keep reloading your save file if you fail) to pretty much guarantee that you’ll get the buff on all of your party members.

If you’re playing on honour mode (or don’t want to save scum), then you might want to put a lot of extra effort into passing this check, potentially even performing a respec on all of your characters. Below is a comprehensive list of methods to improve your odds:

We’ll start off with spells, cantrips and buffs that are easy to access in most playthroughs:

Guidance – a Cantrip that gives +1d4 to a character’s skill checks. Clerics can use this from the start of the game.
Bardic Inspiration – add a 1d8 buff to your character’s Religion check.
Enhance Ability: Intelligence – This spell will give you Advantage on the Religion check, markedly increasing your success chance.
Look out for other boosts unique to your character, class or race, such as Astarion’s Happy buff, which gives him a +1 boost to all skill checks if he bites a living humanoid.

If you want to respec, your best option is to make a build along these lines:

Choose the Bard class
Put your starting Intelligence to 16
Get Proficiency in the Religion skill
At Level 3, get the Enhance Ability spell and ensure you get Expertise in Religion.
At Level 4, get Ability Improvement and put both points into Intelligence
At Level 5, multiclass into Warlock, choosing The Fiend subclass for the Dark One’s Own Luck feature.
Get Ability Improvement: Intelligence again for your second feat.

If you want to go really overboard, you can use these equipment tricks to increase your success chance even more:

Combine the Shapeshifter’s Boon Ring with the Disguise Self or Seeming spell to get a 1d4 boost to all checks.
Equip the Mage’s Friend to get a +1 buff to Religion checks.

Detailed Description of the Mirror of Loss’ Dialogue

The Mirror of Loss has a lot of ambiguous dialogue, making it hard to tell exactly what’s going on.

In this last section, we will explain which of the mirror’s responses are good and which options you should choose for a desired outcome.

When surrendering memories…

You will get a memory in return:
If you get “Disappointment floods your mind. You were sure to succeed Stelmane, but Lord Enver Gortash has stolen your support“, you have rolled the +1 Charisma boost.
If you get “You feel the presence of something, ancient and unknowable. It has taken notice of you.” you have rolled the +2 ability point boost, and will be prompted to choose from one of six slightly ambiguous responses.
If you get any other response, you have failed the roll and will need to try again.

BG3 Mirror of Loss Gortash Memory

When choosing your +2 ability boost…

After getting the “You feel the presence of something, ancient and unknowable. It has taken notice of you.” reply from the mirror, you are prompted to choose which ability you want to boost. Except it isn’t exactly written in plain English.

In my opinion, it’s not too hard to figure out which one is which. But in case you are struggling, here is the required choice for each ability:

Strength: “Claim memories of strength from a long-dead general, who marched under the banner of a vanished kingdom.”
Dexterity: “Help yourself to the memories of a seasoned thief’s most daring exploits.“
Constitution: “Seize the memories of a barbarian, whose mind and body were tempered against hardship.“
Intelligence: “Glean the secrets of a wizard who once stalked the library of Candlekeep.“
Wisdom: “Turn to the wisdom of a drow. Once of Lolth, then of Shar.“
Charisma: “Warm to the guile of a bard who could charm even a dragon.“