Holds the current game mode (0-4). Checked by the routines at 7500 (using the event entry at 5FE0), 7996, 7AB6 and F080, and updated by the routine at F8AE.
Mode
Meaning
0
Demo mode
1
The game has just started
2
Sam has entered no. 15 with the key
3
Sam has had the phone call about the key to no. 74 and gone to the top of the apartment building