BG3 Karlach Romance: All 4 Endings Explained and the Approval Decisions That Unlock Each One

You defended the Emerald Grove, helped Dammon upgrade her engine, and kept approval climbing. Then you finish Act 2, arrive in Baldur’s Gate, and Karlach quietly tells you it’s over.

That’s the Act 2 lock — a timing requirement buried in footnotes across most guides, if mentioned at all. Fail to trigger Karlach’s romance scene before leaving the Shadow-Cursed Lands, and she ends the relationship the moment you arrive in Act 3. No second chances, and the romance-exclusive Avernus ending closes with it permanently.

Karlach has four distinct Act 3 outcomes. One of them — going to Avernus with the player character — is exclusive to a completed romance. Getting there requires decisions that start in Act 1 and stay consequential all the way to the final fight. This guide maps all four endings to the exact choices that unlock or permanently close each one. For a full overview of every companion romance, see our BG3 companion romance guide.

Quick Start: The Romance-to-Best-Ending Checklist

For the romance-exclusive Avernus ending (Ending 3 below), these steps are required in order:

Reach 20+ approval with Karlach before the end of Act 1
Find Infernal Iron and bring it to Dammon in Act 1 (first engine upgrade)
Find a second Infernal Iron piece — complete Dammon’s second upgrade before leaving Act 2
Trigger the romance scene at a camp long rest during Act 2, after the second upgrade
If the Mizora complication arises in Act 2–3, explicitly choose to stay with Karlach
Attend the Singing Lute date with Karlach in Act 3
At the endgame when her engine goes critical, choose to go with her to Avernus

Miss step 4 and you cannot access Ending 3. Miss step 3 and step 4 won’t trigger.

How Karlach’s Approval System Works

Karlach is not complicated to please in principle: protect the innocent, be honest, stand up to bullies, don’t betray your friends. She’s a Tiefling who spent a decade in Avernus under a devil warlord — she reads people fast and has zero tolerance for cruelty or cowardice.

The threshold that matters for romance is 20+ approval by the end of Act 1. One important correction most guides don’t make: the Act 1 nighttime campfire confession (tied to 30+ approval) is currently bugged in Patch 6 and does not trigger reliably without mods. The romance doesn’t actually begin in Act 1 — it begins in Act 2 after the second engine upgrade. Your job in Act 1 is to reach 20+ and hold it.

A single catastrophic choice — betraying the Emerald Grove, siding with Minthara, kidnapping Isobel — can wipe out enough approval to close the Act 1 window. A consistent pattern of cruelty is worse. You don’t need to be perfect; you need to avoid the big failures.

Biggest Approval Gains (Act 1–2)

Action	Gain	Act
Defend the Emerald Grove and talk to Zevlor	+10	1
Allow Dammon to upgrade Karlach’s infernal engine	+10	1
Kill Anders’ false paladin crew	+10	1
Use Detect Thoughts to expose Anders’ deception	+10	1
Call Wyll the best of the group after Mizora transforms him	+10	2
Refuse to open the gate for Minthara	+5	1
Pledge to kill goblin leaders to save the Grove	+5	1
Stand against the gnome slave masters near Nere	+5	2
Tell Karlach she has a real friend in you (Soul Coin scene)	+5	2

One edge case worth knowing: sleeping with Karlach and then calling it a mistake causes a −100 approval crash and immediately ends the relationship. There is no recovery from this choice.

The Romance Roadmap: Act by Act

Act 1 — Build the Foundation (Target: 20+ Approval)

The most reliable path to 20+ approval runs through two quests you’d do anyway: the Emerald Grove defense (+10) and the first Dammon engine upgrade (+10). Find Infernal Iron in the Underdark or near the Blighted Village and bring it to Dammon at the Grove before the Act 1 crisis resolves.

The Act 1 nighttime romance scene is bugged in current patches — don’t wait for it. Just stay above 20 approval and move into Act 2.

Act 2 — Where the Romance Begins (and Can End)

After reaching the Last Light Inn and completing both Dammon engine upgrades, a romance scene triggers at the next camp long rest. This is where the relationship actually starts, and where the most common fail state lives.

The Act 2 Lock — the single most important timing issue in her arc: Leave the Shadow-Cursed Lands and enter Act 3 without triggering this long rest scene, and Karlach ends the relationship when you arrive in Baldur’s Gate. There is no way to reinitiate a romantic relationship in Act 3. The romance-exclusive ending is gone.

The second upgrade requires a second Infernal Iron piece, available in multiple Act 2 locations. Find it and complete the upgrade before making your final push toward Moonrise Towers.

If the Mizora situation arises — she becomes an option while you’re romancing Karlach — choosing Mizora triggers a confrontation. Karlach demands a choice. It’s not automatic ending; you have to actively choose to walk away. Choose to stay and the romance continues.

Act 3 — The Date and the Endgame Decision

Karlach proposes a date at The Singing Lute restaurant in Baldur’s Gate’s Lower City. Attending deepens the relationship’s narrative weight and adds context to what follows. The structural decisions happen at the endgame when her infernal engine becomes critically unstable after the Netherbrain fight.

Karlach and the player character at a campfire in BG3 — the Act 2 romance scene — The Act 2 campfire scene — after the second engine upgrade — is where the romance actually begins. Miss it before leaving Act 2 and the relationship ends in Act 3.

Karlach’s 4 Act 3 Endings: What Gets You There

Ending 1: The Heroic Death (Burns Out as Herself)

Who can get it: Any playthrough, romance or not
Upgrades required: At least one, for the full cutscene
How it triggers: After defeating the Netherbrain, decline all Avernus routes

Without any Dammon upgrade, Karlach collapses without ceremony. With at least one upgrade, she walks to a dock, looks at the city she always dreamed of seeing, and burns out with her identity intact. Community consensus — and the framing of most endings analyses — treats this as the most emotionally honest outcome: she dies free, unchanged, as herself rather than exiled or fundamentally altered.

Romance playthroughs get additional farewell dialogue, but the outcome is identical. At the endgame, the game presents the Avernus options sequentially — actively decline all of them and the dock scene follows.

Ending 2: Returns to Avernus with Wyll

Who can get it: Any playthrough where Wyll becomes the Blade of Avernus
Upgrades required: Both recommended
How it triggers: Wyll accepts the Blade of Avernus mantle; at endgame he offers to accompany Karlach back to the hells

This ending is driven by Wyll’s storyline, not Karlach’s romance. If Wyll is dead or refused the Mizora deal, this option doesn’t appear.

Larian expanded this ending in Patch 2 (August 2023). Where the original version sent Wyll and Karlach off alone, the update added three explicit choices: let them go together, go with both of them to Avernus yourself, or send them alone. If you’re also romancing Karlach, the option to join them creates a three-person Avernus departure — a romantic variation that doesn’t require the solo romance path to unlock.

Ending 3: Returns to Avernus with the Player Character (Romance-Exclusive)

Who can get it: Romance playthroughs only
Upgrades required: Both, before Act 2 ends
How it triggers: After the final battle, you offer to go to Avernus with Karlach yourself

This is the only Karlach ending locked behind the romance. The dialogue option to offer going with her doesn’t appear without an active romantic relationship — Karlach won’t accept the offer from someone she isn’t with. If the romance failed at any point, the choice isn’t on the table at the endgame.

What happens in Avernus is deliberately left ambiguous. The game shows both characters walking through a portal together — heading back into the Nine Hells to keep fighting rather than accepting a quiet ending. Whether that reads as hopeful or grim depends on how much you trust what Avernus does to people.

This ending is the most commonly missed. The two failure points that account for the majority of cases:

The Act 2 lock — leaving the Shadow-Cursed Lands without triggering the long rest romance scene
Missing the second upgrade — not completing both Dammon upgrades before Act 2 ends, which blocks the scene that starts the romance

If either condition isn’t met, the option to go with Karlach doesn’t appear at the endgame, regardless of how much approval you’ve built.

Ending 4: Mind Flayer Transformation

Who can get it: Any playthrough
Upgrades required: None — the transformation extinguishes the infernal engine
How it triggers: During the final confrontation, allow Karlach to undergo ceremorphosis to destroy the Netherbrain

The immediate result: her engine problem is solved, the flames go out, she survives. The longer-term reality: Mind Flayers gradually lose their pre-transformation identity. The Karlach who comes out the other side won’t carry the same personality, memories, or relationship forward in the same way.

For romance playthroughs, there’s specific dialogue before the transformation that acknowledges the relationship — a farewell of sorts, since whoever emerges won’t be the same person. Community consensus treats this as a bittersweet-to-bad outcome, not a rescue, despite the surface-level survival framing.

There’s also a betrayal variant: allow the transformation, then take control of the Netherbrain yourself. This ends with your character killing Illithid Karlach in a cutscene. It’s the worst outcome in her entire arc and has nothing to do with romance choices — it’s a villain path that happens to involve her.

Decision Tree: Map to Your Target Ending

Target Ending	Required Steps	Biggest Risk
Ending 3 — Avernus with Player (romance)	20+ approval Act 1 → both upgrades before Act 2 ends → trigger Act 2 long rest scene → Singing Lute date → choose to go with her at endgame	Leaving Act 2 before triggering the romance scene
Ending 2 — Avernus with Wyll	Keep Wyll in party → let him accept Blade of Avernus deal → at endgame choose to join or stay	Resolving Wyll’s Mizora arc without him becoming the Blade
Ending 1 — Heroic Death	At least one engine upgrade → at endgame, decline all Avernus routes	Accidentally accepting an Avernus option at the final decision
Ending 4 — Mind Flayer	Accumulate illithid tadpole power across Acts 1–3 → choose transformation in the final battle	Not accumulating enough tadpole power for the option to appear

For gear to support the Act 3 endgame fight itself, our BG3 best items guide covers the weapons and armour that carry builds through the final battle.

Frequently Asked Questions

Can you romance Karlach without finding the Infernal Iron?

Not fully. The romance is mechanically linked to the engine upgrades. Without the first upgrade, you can have early flirtation but the Act 2 scene — the one that starts the relationship — won’t trigger. Infernal Iron is a required item, not optional side content. Find it in the Underdark or the Blighted Village area during Act 1.

Does romancing Karlach lock you out of other companion romances?

BG3 generally permits multiple simultaneous romances, but Karlach requires you to own certain decisions. The Mizora situation is the sharpest example — she confronts you and demands a choice. Pursuing Karlach’s Ending 3 while stacking other romances is technically possible but requires managing the disapproval fallout when it arises. The game doesn’t hard-lock you to one companion; it just makes you live with the decision.

I sided with the goblins in Act 1. Can I still romance Karlach?

No, in practice. Agreeing to attack the Grove with Minthara can cause Karlach to leave the party outright, not just disapprove. If she stays, the approval loss is severe enough to close the Act 1 window. The goblin path and the Karlach romance are functionally incompatible choices — you can’t do both.

Which ending is actually best for Karlach as a character?

Community opinion is genuinely split. Ending 1 (heroic death) is most frequently cited as the truest-to-character outcome — she dies free, unchanged, having seen the city she always wanted. Ending 3 (Avernus with player) is the best outcome for a romance playthrough and the only one that rewards the full relationship arc. Both are more satisfying than Ending 4, which solves the engine problem by eliminating the person who had it. No ending is objectively correct — which is the point of her story.

Sources

Michael R.

I've been playing video games for over 20 years, spanning everything from early PC titles to modern open-world games. I started Switchblade Gaming to publish the kind of accurate, well-researched guides I always wanted to find — built on primary sources, tested in-game, and kept up to date after patches. I currently focus on Minecraft and Pokémon GO.