From the FERMI RESOLUTION RPG Worldbook: Technology Hand-waving Made Simple.

Getting some good feedback from people.

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Technology Hand-waving Made Simple

At some point, a player might ask about the state of the roads, or point out that ruins tend not to stay intact for thousand years with only a little dust to show for it, or bring up something that the GM had not even considered (one example that came up in playtesting involved the vast arrays of fiber cables buried all over the country). Below are a few ways to handle such pesky incongruities.

The Collaborative Hand-wave. This is the favored solution, obviously: get the player to tell you why things are anomalous. In fact, bring the entire party into it, and reward their creativity with a mild but not adventure-sabotaging benefit. This reinforces player engagement and immersion, which is rarely bad. Use the other two options below for when nobody can come up with a good in-game reason on their own.
The Pre-Discovery Hand-wave. The Discovery’s ‘official’ date of 2103 AD is not accidental: it allows for eight decades’ worth (at the time of this writing) of future technological and societal change. Many things that were ubiquitous in 1940 are utterly absent in 2020; it is reasonable to assume that the same will be true when comparing 2020 to 2100. Any number of missing resources can be explained that way. Likewise, a pre-Discovery artifact could be made of durasteel or transparent aluminum or some other buzzword.

The First Age Hand-wave. It is canonical in this setting that most of the 22nd Century’s energy sources were magically wrecked in the first days of the Discovery, typically by mages literally gone mad with sudden power. It is entirely reasonable that there might have been magic users out there who hated, say, the Interstate Highway system badly enough to curse it so thoroughly that it, and their brains, exploded. That same First Age magic might have been used to preserve, too. Government and corporate groups would have been trying to research the new physics until civilization fell, and possibly afterward; exploring the aftermath of one of their experiments could reveal anything.

When all else fails: just run with it. If the players want to take over the Midwest themselves by turning every overpass into an Adventurer’s Guild stronghold, well, maybe the Universal Dominion should have done that first. Or maybe they tried, and the reason why they didn’t is now the adventure.

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