Shadow of the Tomb Raider

This achievement is story-related and cannot be missed. You will unlock it towards the end of game.

You'll know when you're getting close. Story progression will lead you back to The Hidden City in Paititi. You'll have to talk to Etzli once you're ready for the final mission. A warning will pop up letting you know you can't turn back or fast travel until the last mission is completed.

Continue with the mission and eventually you'll come face to face with an unlikely ally.
The achievement will unlock once you're done talking to your newest buddy. Cheers!