A fan mod by Sean Gugler
You can play online right now:
deathmaze.dsk from https://github.com/sean-gugler/DeathmazeFairPlay/releasesWhen the disk boots, choose option 4 to play the Fair Play edition.
Stuck? Try the self-guided, minimal-spoiler hint page.
Deathmaze 5000 was released in 1980 by Med Systems Software for the TRS-80 and Apple II platforms. We would describe it today as an “escape room” experience; players are tasked with navigating a maze, manipulating objects, and solving puzzles with the purpose of escape. This was a novel mash-up of play elements at the time. Maze games and text adventures already existed but I am not aware of any earlier example than Deathmaze 5000 that combined the two formats.
The writing was quite clever, but suffered from moon logic, items with no purpose, unfinished puzzles, and some inconsistent behaviors. When I finally solved it after 40 YEARS of trying, I was both satisfied and disappointed. I decided I could make it better. Armed with my recent technical experience disassembling Ultima IV, I wove the loose ends together and improved the structure of the weaker puzzles while retaining as much of Deathmaze’s original material as I could. I also patched up a small handful of bugs discovered along the way.
The “Fair Play” edition reflects my sensibilities on what consitutes fair puzzle design. My alterations attempt to be consistent with the original writing tone and style. To the degree I’ve failed, I ask your humble forgiveness.
This project builds four editions of the game:
All four are included in the provided disk image for easy comparison.
WARNING: The original game (editions 1 through 3) saves the game directly to track 3, sector 0. This is safe on the provided disk because I’ve allocated a “RESERVED” file to protect that sector. The same may not be true if you copy the files to another disk, so be careful! The safest (though wasteful) thing to do is use a completely blank disk for saved games.
The Fair Play edition saves the game to a proper DOS file through ordinary catalog allocation. This edition and its save file are safe to transport by ordinary means to any other disk. Probably won’t work in ProDOS, though.
The original game required saving to slot 6, drive 1. The Fair Play edition will save to the same slot and drive the game was launched from.
]) instead of the MONITOR (*).The earlier release has been in my own collection since 1980. It is not an official retail disk, so I have no way of knowing for sure if it was cracked or if the original was not protected. There is no evidence of any vanity vandalism typically inserted by crackers, though.
The later release was found on Asimov, bundled on a disk with some other games. The “save game to disk” feature does not work in situ; it relies on standard DOS, but that disk uses “Beautiful Boot” instead. When I transplanted the entire program file to a standard DOS disk, I found that saving worked fine. I have no other information on this edition’s provenance but forensic analysis suggests it was an official update. There are many jump-offset changes which typically result from recompiling source rather than hacking.
The original authors used 1-based indexing ubiquitously, rather than machine-friendly 0-based indexing. In many cases this means setting up data table pointers to the address one entry earlier than where the table actually starts.
The original authors used the assembly code instructions bpl and bmi after cmp, rather than the customary bcs and bcc. In the general case this is bad practice, but it works in Deathmaze because the numbers being compared are always unsigned 7-bit values (in the range 0 <= A <= 127). (Read more about 6502 comparison logic at http://www.6502.org/tutorials/compare_beyond.html)
The game was originally written for the Z80 instruction set of the TRS-80 and ported to 6502 for the Apple II. This could explain certain anomalies, such as always using indirect addressing with indexing (lda (ptr),y) rather than absolute indexing (lda addr,x) where possible, or why the A register is used as an intermediary for loading values into X and Y rather than using ldx and ldy.
Time spent: 10 weeks
I used Regenerator 1.7 to disassemble and hand-label the binary program.
Literally one hour after I first published my work to github I coincidentally discovered Andy McFadden’s excellent disassembly listing. From there I also discovered his tool SourceGen. I probably could have finished this project a few weeks sooner had I known about those. Oh well.
Andy’s copy of the game appears to exactly match the retail “Rev1” I have, except for one curiosity: his edition saves the game to Track 2 Sector F. This change is not present in “Rev2”, it still saves to Track 3 Sector 0. Since Rev2 is clearly an official release, having changes that could only result from recompiling from source, I’m inclined to think Andy’s edition is a fan hack of Rev1 made to protect the saved game against conflicts with the file storage area of the disk.
https://github.com/sean-gugler/DeathmazeFairPlay
This source code has been reconstructed by disassembling and symbolicating the 1980 binary code released for Apple II series computers. It likely bears little resemblance to the original source, but it can be used by modern tools to build the same playable binaries.
To build from the source you need this software:
My development environment is Windows Subsystem for Linux, Ubuntu flavor … although any Linux should do.
Type make all to produce a DOS 3.3 disk image in the output folder.