ShadowFinder is a concept for a Modern Urban Fantasy setting using heavily-modified Starfinder.
The idea behind ShadowFinder is that there used to be magic in our world, but it went away when the Gods of Old Egypt left to go a place Beyond. Then there was no magic to speak of, until a group of mystic champions arrived in Siberia during WWI to kill Rasputin, and accidentally left a few magic devices behind.
Now it’s the Modern era, and magic is common enough that most governments and many international organizations have at least one department that knows about it, and as needed deals with it. But the greatest protection a mundane creature can have is to believe magic does not exist, and so these in-the-know groups are literally protecting the world by keeping magic a secret. Further, just as vampires cannot be seen in mirror, they (and all magic effects and creatures) cannot clearly be recorded or sensed by any camera, film, or recording device, but are vulnerable to atomic weapons. So magic threats tend to try to stay out of sight, so they don’t force the whole world to grapple with their existence and potentially over-react with devastating power.
Both sides work to keep magic in the Shadows, and to find sources, allies, threats, and lost relics in those shadows to bolster their own side in a never-ending was keep just out of sight.
Classes would be drawn from various sources. Soldiers and operative from the core rulebook, certainly, with little change. Likely mechanics, but with neither drones nor exo-cortexes as common options, replaced with some other variable class feature. No solarions or vanguards at all, but maybe sword saints. Warlocks and witches seem more appropriate than mystics or technomancers, though it’d be a shame to not have some kind of modern-device-focused spellcasters — again variant classes might do the trick. Biohackers are out, witchwarpers likely in. The precog is a definite maybe, depending on how it turns out.
Weapons would scale differently, with an equipment list that didn’t assume you got higher- and higher-level weapons, but instead use weapon damage benchmarks to scale up the damage a character does as they gain levels, allowing things like pistols, shotguns, and rifles to retain utility even at extremely high levels.
In a standard characters would at least initially be part of one of the groups that monitor, track, and if needed neutralize supernatural threats, and action would primarily take place in wilderness areas, abandoned towns, lonely highways, and defunct sewers, basements, and subway lines. As players got used to how the ShadowFinder world worked, some scenes might burst into the bright light of day, only to be misconstrued by the public (and maybe even misremembered by witnesses) as gas main explosions, terrorist attacks, or herds of feral hogs.
Plots could include locking down viral zombie outbreaks before they turn into zombie apocalypses, retrieving the book that got moved to a university’s accessible library that is bring people’s nightmares to life, undead serial killers that haunt campgrounds, tracking down wererat colonies that are feeding on the homeless, rescuing student filmmakers from nighthags in the woods, capturing souls that have escaped hell, slaying evil clown demons, and racing against time to beat cultists to the artifacts of power in the bottom of dungeons built in the ancient era to prevent them from falling into mortal hands. Along the way other weirdnesses might be encounters, such as cannibalistic humanoid underground dwellers, giant alligators in the sewers, giant cockroaches mimicking humans, and genetically engineered giant spiders.
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