One pass is: the keys that are not the knight's own (walking, jumping, fighting, picking up and dropping are read in his update, CREATURE_UPDATE); LIFE printed if it has changed; the message line (SHOW_MESSAGE); and each record from the knight's, the seventh, to the last in use updated by the author's CHE3D (CHE3D). Nothing waits for the frame, so a pass takes as long as it takes. The author's source text, left on the tape, names the places from the use of a thing on: STAR2, USE6 to USE4, ST20 to ST22, STE3, ST3 to ST6 and ST9.

The keys, in order. 9 turns the Kempston joystick on or off (bit 3 of OPTIONS), and waits until no key is held. After a room's first pass its colours are put on (ATTRI) -- it was drawn black on black -- so it appears all at once, and the thing in use is shown again. Then, unless the joystick is being pushed: SPACE and SYMBOL SHIFT together pause the game until a key is pressed; SYMBOL SHIFT and 0 together return from ROOMST, which ends the game; 6 or 7 use the thing in the chosen place; 1 to 5 choose a place and show what is in it.

What using a thing does depends on its kind (+12). Kind 9 carries the knight off to room 30, to where a new game starts him (TELE, TITLE_SCREEN), after SAVE_OBJECT_POSITIONS has saved the room. Kind 6 makes LIFE 99. Kind 5 freezes the room's creatures until he leaves it (bit 7 of GAME_FLAGS: CHE3D then lets everything but the knight only fall). Kind 4 adds 10 to LIFE, to no more than 99. Each of these is used up: its place is emptied, though its record stays among the room's, hidden, and its entry in the object table says room $FE; LIFE is printed again. A thing of any other kind does nothing.

A pass ends with a RET when LIFE is 0: that returns from ROOMST to TITLE_SCREEN, which says GAME OVER.