September 2016 had the challenge to create a store and storekeeper for a game.
Ember's Shoppe of Magic and Wizardry
Ember's Shoppe is a dirty back-alley shop run by Ember, former apprentice. Ember's not a proper wizard (he's capable of casting a few cantrips), but he knows magic, and has built himself into something of a minor sage (he has the equivalent of a minor category of Dweomercraft, with no major category). Since the sagely business isn't steady, he instead makes his living as a talismonger... a man who collects and sells the necessarily material components for spells and magic items. Want some glassware to open a potions lab? Ember may have it in stock. Special quills for scroll writing? He has a few, come take a look. Not really wanting to crawl around in caves for your own bat guano and sulphur? He rolls easy-to-cast balls of them and will sell them to you. He may even have some scrolls and potions that he'll sell.
Ember's shop, however, has an evil reputation. Because Ember is not a proper wizard, any scrolls he attempts to use himself (that are not otherwise available to everyone) have a flat 25% chance of failure... often, disastrous failure. While not properly addicted to magic, he is borderline obsessed and very enthusiastic. Ember doesn't leave things alone, and he's prone to try to use scrolls he acquires, if they're not sold quickly. After accidentally summoning mezzodaemons and setting off one too many fireballs, he was given a shop of stone in the poorer part of town by a local wizard who relied on him for material components. The local guards hate him, regarding him as a danger, and are likely to follow, and perhaps harass, anyone consorting with him to "see what they're up to." The local magic-users, including some of the less-established priesthoods, see him as truly useful, if a bit misguided.
Ember's primary stock-in-trade is spell components. For spells in the Player's Handbook, there's a 1d20% chance per spell level that he won't have the resources readily available (so, if wanting the components for a Resurrection, there is a 7d20% chance he cannot get it at all). He tends to charge about 10% above the value of the items for anything he sells, and frequently works as a middleman for more expensive components, rather than a retailer, so it might take a few hours or days to get the more valuable material. Things he does not have in stock, he will still require payment in full up front, and will keep 3% for his time, even if he can't get the items. He's quite up front about this.
The interior of the shop is brightly, magically, lit, and some of this leaks through the door. Despite that, it still manages to be a bit chill and damp, as it's essentially a large stone bowl, turned upside down and with a door chopped into it. Ember also has a well inside, contributing to the damp, and no sign of how he may cook his food, save a soiled dish he keeps out of sight. Most of his storage is in the cellar (which wraps around the well, should you go into it), with the ground floor room containing his study, his bed, and a few common components he keeps on hand. There are a number of magical protections on his shop to discourage thieves, carried out in trade with spellcasters he's done business with.
Ember himself is very reputable in the magic world, and has a few minor magical items that help him in his work. He can't brew potions himself, but he is also something of a fixer for alchemists-for-hire, and has fostered a few promising children until they can find apprenticeships. He seldom sleeps and wakes quickly, any time, day or night, though he grows testy if there's nothing of interest to him. He'll talk animatedly about magic for hours, if allowed, and ask probing questions about spells and magical devices when they're brought to his attention. Somewhere along the way, he acquired a large rat as a familiar, and he's not always quick to clean up rat droppings when he's busy, though he can do so with a cantrip. It is unclear why he's not a full spellcaster; he's smart enough and has the basic ability, but lacks a certain something, and none of the local wizards have been willing to finish his training after whatever happened to his master, which they all proclaim ignorance of. For his part, Ember is not particularly interested in pursuing a practical education in magic, being quite content with his sagely knowledge and magic tricks.
Ember's Shoppe should be placed in a major, relatively cosmopolitan city; simply not enough call for a man of his talents in every Hommlet and Shadowdale in the spheres. He takes coin of the realm, or drafts on local banks (he, himself, banks with the local deity of trade). He's also open to trade, but makes his own determination about the value of trades. He likes magic items, even potions and scrolls, and is able to use most magic items, even those usually restricted to specific classes. He'll sometimes trade spell components for those willing to identify magic items for him, or provide other magical services. He has a few spellbooks, taken in trade, and will sometimes sell the right to copy from them, though they tend to have only very basic spells... more valuable spellbooks, he sells to wizards he knows after learning what he can from them.