The Game: Would-be digital dungeon masters can reshape the world of the most powerful Apple II adventure game of its era – Exodus: Ultima III – in their own image, from changing the coastlines of Sosaria to changing the behavior of its inhabitants. Cities and townes can be completely redrawn, and the deadliest denizens of the world can be unleashed anywhere. (Dan Gartung, 1984)
Memories: With Ultima III acknowledged as the ultimate adventure game for the Apple II by most 8-bit computer RPG enthusiasts, the ultimate challenge was to forge ahead and see the hazardous quest to its completion. And after that? The next challenge was to assume godlike power over the world created by Lord British.
Very much unauthorized by Origin Systems, Richard Garriott or any other entity associated with the Ultima saga, Dan Gartung’s Exodus Construction Set creates a user-friendly means to peel back the complex layers of code that makes Ultima III the masterpiece that it is, and allows users to rewrite the game’s DNA at the most fundamental level, from a text-based “paint” program for redesigning the world down to the city/town level, to the thing that can completely alter the balance of the game: changing the variables at the heart of every type of monster that can be encountered in the game. You name it, Exodus Construction Set could do it, and happily save the results either on the Ultima III master scenario disk (not recommended, for the record, since that would wipe out the original Sosaria map and variables that serve as the baseline for any alterations) or on another floppy. The controls in some modes, especially the “paint” modes, weren’t terribly user friendly, but when you’re peeking under someone else’s hood you should only expect so much help.
Gartung sold the Construction Set himself, via small classified ads in magazines such as Nibble; whether his sales ever reached enough of a critical mass to cause any consternation in the real-life kingdom of Lord British, this writer simply doesn’t know. Gartung also released an Ultima III Character Editor, allowing one to level up one’s existing characters to their 
own godlike status – theoretically, between the two products, one could create an impossibly tough world and then plow through it with a quartet of improbably tough player characters. These kinds of products were hardly new in 1984; a Wizardry character editor/resurrector program called WizFix had already made the rounds by then.
In the end, did Exodus Construction Set have any far-reaching effect? Probably not. The same year, Electronic Arts published Adventure Construction Set, allowing budding gamemasters to create their own universe from the ground up. The games created with ACS were still of the god’s-eye-view, top-down-view variety, just like Ultima III, but would-be game makers weren’t limited to Ultima‘s built-in tiles, monsters and weapons. Exodus Construction Set might have inspired a few hearty adventurers to take on programming 
themselves, once it demonstrated that even a complex game like Ultima III was all about variables, statistics, record-keeping and randomization… but for most, it probably placed the game’s climactic scene within reach, or gave them a chance to play, if not God, then at least Lord British, for a day.