Will-o-wisp

Tiny, flickering balls of glowing light that barely illuminate their surroundings- in fact, everything more than ten feet from them seems to get even darker  They appear mostly in the lands surrounding domains, so that non-fairies who have distant fairy neighbors are the most common witnesses, but sometimes will appear at dusk in a place where a small wormhole just closed, anywhere in the world
They don’t appear within a 1-mile radius of permanent settlements
They are drawn to individual travelers or small groups of people, who are feeling a bit lost (if no such person is nearby they just linger in the air, slowly fading)
There is a 66% chance that they will lead the lost person or persons toward a path that leads where they want to go
There is a 22% chance that they will lead the travelers farther away from civilization and toward a natural danger (cliffs, caves, fallen logs that trip you and bash your legs as they do so, steep slopes of rain-slicked grass & mud, slopes of loose rocky debris, etc)
There is an 11% chance that it leads to another lost person or a corpse (whichever’s closer)
There is a 1% chance that it leads into a random wormhole and drops its victims in a random part of the world
If you try ignoring a wisp, it will hover in your peripheral vision, still darkening its surroundings and limiting your visibility, occasionally darting across your path
They will only leave if you feel confident in your location (unlikely, with initial confusion & a wisp to trip you up), approach it with aldrum (iron makes it flicker more), follow it where it leads, leave one environment (i.e. a forest) and enter another (like a moor or settled land), or ignore it until dawn
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Mortals seeking to defend their communities in faerie lands: the greatest among them will attract friendly tiny will-o-wisps. If you collect more wisps over time, these will slowly begin to form an ambient force that offers tips and tricks. Those who train with these wisps become Rangers (eventually Swarm Rangers) These ranging skills can be taught, and those who collect enough wisps can become swarm rangers as well. Those who do not collect wisps or practice beyond fey lands become Hunter Rangers