i have been working on some planning for the jam, and writing some pseudocode.
the game is meant to be quite mind bending. i got the idea from 'cocoon', a game i played on my xbone.
in cocoon you have orbs which contain worlds. you can teleport in and out of them. you can then place these orbs inside others.
in my game it is similar. you can teleport into a bag, carrying an indeterminate inventory. you may, for instance be carrying a bag that contains a shop, a castle, a village, other bags...
the code will draw from an old BASIC game called CHASE that i ported to common lisp, and the common lisp text adventure i wrote while i was still learning.
the concept is simple enough: CHASE is a one-screen game about avoiding robots which take a step closer to you every move you make. they will happily collide with electric fences inside the playfield, so the game is terrifying but possible to win.
the text adventure will have its inventory system repurposed: you search for items within a list held in memory with the famous ASSOC, and merely PUSH new items onto the end of that list. this is potentially slow given the size of the inventory, but there really is no need to be clever here.