Lost in Random

This achievement is unmissable. This achievement pops after you complete the introduction. You'll go through a sequence where you learn basics about combat. Right after, you'll go through an introductory scene where you follow a character across a number of wooded planks. You'll know you're almost at the end of the intro when you arrive at a teapot shaped building. Skipping all the cut scenes, it was about 6 minutes from start of game to finish.