Ghostlore

The achievement description is misleading. I worried that this was bugged when I started the level (the first after the intro / prologue), but this actually unlocks at the end of Pulau Hijawan after you defeat the boss. When the achievement pops, it will instead read "Reach the end of Pulau Hijawan."

It should take about an hour of playtime to get to this point. It is aligned with the story and cannot be missed.