The castle, worked out from its doors. The game itself has no map and no idea of a floor: every room has a list of what is in it (ROOM_CONTENTS), a door is two records eight bytes apart, one in each room it joins, and the wall it is on is in its own +$05. So each room is put beside the room it was reached from, on the side of the door, and a staircase or a trapdoor takes it to another floor. Every room is drawn by the game itself, with what is in it as a new game sets it out, and links to its list, where it is shown larger. ★ is room $00, where a new game puts the player.

Doors are grey, locked doors their colour, and the knight's clocks, the wizard's bookcases and the serf's barrels dashed. ▲ and ▼ mark the way to another floor, by stairs or trapdoor, with the room it leads to. The floors are numbered by counting stairs and trapdoors from room $00: which way a staircase goes is not written anywhere either, and the reading that leaves the fewest doors out of place is that its big door frame is a floor above its other end.

The castle does not quite lie flat. 6 doors join rooms that no single choice of floors puts together, and a few corridors loop round, so some doors are long lines and some rooms have been moved to the nearest free square: ⇆ marks a door whose other side is somewhere the drawing could not put beside it.

The markers along the top of a room are layers, each ticked on and off below. They are read from the game's own records the moment START_GAME has set a new game up -- after PLACE_ACG_KEY has hidden the A.C.G. key, PLACE_KEYS has placed three of the coloured keys and the mummy, and the template has been copied into place -- and each thing is told by its handler: what PICK_UP runs for can be carried, EAT_FOOD is food, MUSHROOM a mushroom, and the big five each have a mover of their own. The trapdoors and the A.C.G. door are the doors of those types. Hold the pointer over a marker for what it is.

This is the first game after loading. The key pieces and three of the keys are placed by the frame counter, and the frame counter does not move on the title screen, so the first game is always set out alike (FRAMES $256F in this build's snapshot); later games differ, and the key below says where else each could be. The names of the other collectables describe their pictures on the Sprites page: the game has no words for them.