The ROM's system variables, as the BASIC loader left them. The game reads only two of them, and both were loaded from the tape rather than set by the ROM. FRAMES, from the tape's last block: the game checks its middle byte (START, the first of the three protection checks) and starts its turn counter from it at every new game (NEW_GAME); since interrupts stay off from the loader on, FRAMES never counts on, and every game starts its counter from the same value. And NMIADD (NMIADD), where the tape put the JP (HL) the game dispatches through.