From the introduction:
You awake and see nothing. You wave your hand in front of your face and still nothing. You stand and hurt your naked legs on the rock floor, then hit your head on the low ceiling. You reach out to grab something and slip on wet rock. You are blind, wet, naked, hungry, and lost. You are in the blackest cavern.
In this game, most of the players will play people lost below the earth in a cave. One person will be the Game Master, who will be in charge of describing the environment to the other players.
Unlike in many roleplaying games, the characters in this game cannot see, at least initially. They are in a space with no light and are completely blind.
In this game, it is assumed you are in a fantasy world with goblins, kobolds, trolls, swords, and magic. This assumption does not have to be kept, however: this game can be played completely straight with no supernatural elements.
User summary:
This rules-light adaptation of Apocalypse World adds in a special mechanic for "Memories", a variant on the "Dark Memories" rule.