This achievement is one of the hardest to get right during your playthrough. Here is a rough list of tieflings and where to find them throughout the game. The bottom line is you need to make sure every tiefling in the game survives one way or another. Avoid going for this during your Dark Urge playthrough.
Emerald Grove: Act 1
- Don’t kill Lae’zel’s captors.
- Heal the tiefling being attacked by the bugbear.
- Save the tiefling child from the snake in the druid grove.
- Save the tiefling child from the harpies on the east coast.
- Avoid bringing the battle with the goblins to the Emerald Grove.
- Don’t let any tieflings die in combat.
- Heal the tiefling in the storage room.
- Roland’s adventurer group should stay to ensure the others survive to Act 2.
Last Light Inn: Act 2
- Keep Isobel and the tieflings alive during the fight at the Last Light Inn.
- Save the tieflings in Moonrise Towers Prison before finding the Nightsong.
- Save Roland when he leaves to find his siblings.
- Save Arabella and invite her to your camp. Then locate her parents’ bodies and follow Withers’ advice.
- Save Zevlor from under Moonrise Towers in the Mind Flayer Colony.
Baldur’s Gate: Act 3
- Meet the tieflings in the refugee camp.
- Meet Alfira and Lakrissa in tavern.
- Kill Lorrokaen and keep Roland alive during the fight.
- Steal Mol’s contract from Raphael.