original disk scan is MISSING, this crack download is segmented 100X for no space gain and its OS/B requirement is particular to this file, (other) Aquatron run on XL/XE hardware. In fact this game was developed as a 16K cartridge and published on disk in a last minute change. I converted it back to a 16384 byte cartridge image and the only thing that broke down was the high score list, the one thing most expected to be different in this situation; then I fixed the high score list ;) In addition to keys 1-4 for players & 'S' for sound, <ESC> key pauses, then any key unpauses (where's the "any" key??)
A very good take on Williams' "Defender" (see also game "Repton"). Once again here we have that magic number "1983", mind numbing how so many killer A8 arcade games were made year 1983, the pinnacle of creation in the USA. Paltry is the whole body of work 1982 and older. It took folks 3 years to learn how to program Atari, then, people migrated to 16-bit hardware starting in 1984. 1983 was the (briefest) golden age.
Yes, the "Base" (zeppelin) is yours, it also represents the one reserve life you begin with - the number "1" top right. Destroy the zeppelin (zero points) and you lose your reserve life. After "1" comes an arrow showing the shortest path to Base, that arrow glows in warning when supplies get low. Strengthen shield by collecting presents on parachute dropped from zeppelin. There is an ammo supply counter, but I can keep shooting on empty. Was a cheater added to this cracked file, or is game incomplete? No explosions underwater (submarines plus yourself included) seems unfinished. Bug in (my) emulator: graphical glitch horizontal line on left end of ammo meter, not in our screenshots, it's my emulator messing up the Display list - I doubt it affects gameplay ammo supply.
High score list was programmed to be saved to disk (sectors 190 & 191) but this file version has the writes disabled however imperfectly. They changed the "W" write command to "S" status, so floppy disk drive Status can now cause an error which cancels: an explosion sound & screen fade when a new top ten score is done being entered. Unless the Demo Mode ended by way of completing the level, in which case the sound & fade are skipped normally. If "COMPUTER" dies in Demo Mode and earns a high score, there should be sound & fade after it presses the Enter/Return key.