From the introduction:
Much like a mind palace is used to remember facts about the real world for later recall, The Dream Palace is a place that anchors certain aspects of a Dream World which will be created by you and your friends through play.
This minimalist game is relatively free-form and requires players to maintain an organized collection of images in a common location. This can be a tabletop of index cards or an online wiki, depending on the style of play desired.
This item should not be confused with the similarly named but distinct Dream Palace (Beta).