Baldur's Gate 3 Karlach Romance Guide: Infernal Iron, Act 2 Lock-In & Act 3 Date

You can flirt before the celebration — especially after Dammon’s first repair — and those choices can raise approval, but they do not by themselves move the relationship into Dating on the current unmodded route.

Act 1 flirting still matters for approval and tone, but the current unmodded romance start is the tiefling celebration.

Recruit Karlach on the Risen Road and resolve the Paladins of Tyr conflict. Dammon at the Emerald Grove can use Infernal Iron for the first engine upgrade. After the repair, the dialogue where the player says they still cannot touch Karlach and admits they want to is a large approval/romance-flavoured beat, but the route is not formally Dating until the current celebration start fires.

Dammon is the mechanical gate for Karlach’s Infernal Engine progression and must survive into Act 2.

At the celebration, speak to Karlach and choose the romantic response. Current celebration scripting lets the player tell her how much they like her; if selected for the night, she visits after everyone sleeps. The engine is still too hot for normal contact, so the scene is built around wanting intimacy without being able to touch safely yet.

Do not keep waiting for the old standalone night-visit scene. That standalone visit is bugged; the celebration starts the romance without mods.

Act 1 Karlach intimacy is constrained by the engine; the relationship can start before safe physical contact becomes possible.

At Last Light Inn, give Dammon another Infernal Iron for the second upgrade. Karlach can finally touch others safely. The critical next step is to Long Rest until her evening romance event actually plays. If higher-priority camp events are queued, it may not be the first rest. Keep resting rather than interpreting silence as a broken route.

This scene is the Partnered transition. Partnering with another companion before it fires ends Karlach’s relationship; a bug can prevent Karlach from giving the normal “choose me or them” confrontation, so the player may not get a recovery choice.

After the second engine repair, Karlach’s Act 2 camp scene is the real relationship lock-in; repair alone is not enough.

If Karlach’s Act 2 evening scene has not happened before leaving Act 2, she ends the relationship when Act 3 begins. After The Chosen of Shar is completed or progression goes too far, the solidifying event can no longer trigger. Treat “second repair + camp scene” as a checklist item before the Shadowfell/Act 2 point of no return, not something to clean up later.

Last Light is the safe place to complete Karlach’s second engine upgrade and then clear the camp-event queue before the Act 2 finale.

After entering the Lower City, Karlach asks for a real first date at the Singing Lute. Dinner is a role-play scene rather than a mechanical test: the two characters pretend to be meeting for the first time, ask questions, talk about love and the future, and Karlach eventually professes her commitment. She rents a room upstairs; the player can choose sexual or non-sexual intimacy without ending the relationship.

The Lower City date is the Act 3 payoff: dinner, commitment and optional private intimacy rather than another repair quest.

Encounter | Effect / warning

Halsin | Karlach can consent to a concurrent Halsin romance when asked through the correct dialogue.

Drow twins | Karlach declines the foursome setup; reactions to individual one-off encounters are different.

Mizora | Triggers a serious confrontation. The relationship can survive or end depending on the response; do not treat the encounter as consequence-free.

Emperor / other one-offs | Check the specific companion reaction; one-off intimacy is not the same system as a second full romance.

1. Recruit Karlach and resolve the Paladins of Tyr.

2. Keep the Grove and Dammon alive.

3. Use Infernal Iron for the first repair.

4. Start the romance at the tiefling celebration.

5. In Act 2, reach Last Light and complete the second repair.

6. Long rest until Karlach’s commitment/intimacy scene actually plays.

7. Only then proceed through the Act 2 point of no return.

8. In the Lower City, accept the Singing Lute date.

The old pre-party night scene is bugged in an unmodded game; use the celebration.

Two engine upgrades for the romance progression.

The Act 2 long-rest scene after the second Dammon upgrade.

No. Missing the Act 2 scene closes the route.

Yes, through the consent dialogue.

No. Non-sexual intimacy can preserve the relationship.

The lock-in is the Act 2 long-rest scene after the second Dammon upgrade — repair alone is not Partnered. Long Rest until her evening romance event actually plays. If the scene has not happened before leaving Act 2, she ends the relationship when Act 3 begins.

After entering the Lower City, Karlach asks for a real first date at the Singing Lute: dinner, commitment and optional private intimacy rather than another repair quest. Choosing no sex does not end the romance.