You may have noticed leprechauns in a number of my entries. This isn’t an accident, and not just because I’m partial to the Fey monster type. It’s that leprechauns are easily among the most accessible faeries as well.
Back in 1e and 2e of the world’s oldest role-playing game, almost all the fey (quicklings aside) were relatively benign. After the 3.0 Monster Manual clear-cut its way through their ranks—(much love to Skip Williams & co., but seriously, it was butchery)—the new fey introduced in subsequent books tended to be wild, malevolent spirits of nature—wicked tooth faeries that claimed their ivory booty by ripping the molars out right of your skull BWAHAHAHAHA!!! And even now most fey tend to teeter-totter between these two extremes.
Not leprechauns. They’re—as the gossip magazines put it—just like us. They like gold…probably a little too much. They like drink…enough that they have a whole subrace, the clurichauns, who are spirits of the brewery. They like pranks and a good tale…and one is often the start of the other. And rather than lurking exclusively in the deep woods, they’re quite suburban fey who like the finer things in life and are happy to sneak a pint at the local pub before scurrying back to the woods.
In other words, they’re not particularly good or evil, friendly or foreign. Frankly, they’re little d--ks…just like us.
A leprechaun does, in fact, have a pot of gold hidden at the end of the rainbow—the mists over the Selkie River rapids cause a rainbow to manifest on most sunny days, and Killian Silvertongue has hidden his stash in a cave on the far shore. Unfortunately, a minotaur has claimed both the cave and the gold. Killian needs to convince a party of adventurers to help him recover his treasure without costing himself one shiny yellow piece.
Female leprechauns are rarely seen and are treasured by their kin. When Róisín (ROSH-een) O’Dell falls in love with the halfling river pirate Finbar Half-Ear, it’s a scandal. Half-Ear gets a party of adventurers to help her elope, and from there it’s a race back to his boat, where a cleric stands ready to marry them. But even staying on the handkerchief-marked path is no simple matter when up against a family capable of casting fabricate and major creation, not to mention any number of illusions.
Tricksters they may be, but leprechauns love their homeland. When a pair of dandasuka rakshasas begins doing their bloody work in the ports of Mhaonaigh, the mayor hopes to enlist the devious and magical aid of the leprechaun clan that hides in the nearby hills. The young adventurers he sends must first contact a leprechaun (saving the one who lives under Cobbler Lane from thugs from the catfolk thieves’ guild is a good start), then convince him to lead them under the earth, where (while reduced), they will have to fight mite pests, harvest mushrooms from the back of a giant caterpillar, and beat the leprechaun chief at darts or a shillelagh duel.
—Pathfinder Bestiary 2 177
Hurricane Sandy. It’s on 4 realz, yo.
But what about the leopard? Did that.
In Golarion, gnomes and leprechauns might be closely related, with the leprechauns very studiously avoiding whatever sin cost gnomes their fey natures.
Finally, I’ve mentioned before the amazing—seriously, get yourself a copy—PC1 Tall Tales of the Wee Folk by John Nephew, which did a good job of integrating Greek and fantasy woodland beings with Elizabethan faeries. One of the neat elements from folklore he incorporated was that leprechauns, like most faeries, could turn invisible at will…but only if they weren’t being watched. As long as an enemy had line of sight on a leprechaun, it was stuck visible…but if it could duck around the corner or slip behind a thistle, poof. I think that’s the perfect kind of detail to aid to Pathfinder’s incarnation—it makes them have to be that much more talkative, conniving, and tricky until they can find a reason to—hey, look behind you! *poof*