Week 2: Faucets and Sinks

The two pipes every game economy runs on — where currency comes from, and where it has to go, or inflation eats everything else you designed.

1 March 2027

Every unit of currency in a live game has a birth certificate: a quest reward, a mission payout, a mining tick, a daily login bonus. Every one of those is a faucet. If faucets ran unopposed, the currency would inflate until it was worthless — which is exactly what “gold farmer” panics and “the market is broken” complaints usually are: an economy with more coming in than going out.

Faucets#

• flat: same payout regardless of player skill or time invested — World of Warcraft’s daily and weekly quest turn-ins pay the same gold whether a level-10 alt or a max-level main does them
• scaling: payout tracks player power, which means it scales with inflation itself — EVE Online mission bounties get larger as a pilot flies bigger, more expensive ships, so the reward inflates alongside the cost of playing at that level
• market-adjacent: currency created by selling something to an NPC buyer at a fixed price, which decouples that item’s price from player demand entirely — Old School RuneScape’s General Store buys back common items at a set price no matter how flooded the market already is

Sinks#

• repair and maintenance: durability loss, ammunition, consumables — currency that leaves just by playing normally, whether that’s EVE’s ammunition and module losses in combat or OSRS’s food and potions burned on a single boss trip
• market taxes: a cut taken on every trade, which is also a sink that scales with how active the economy is — OSRS’s Grand Exchange tax takes a flat percentage off nearly every sale
• vanity and prestige: cosmetics priced deliberately high, because the point is that most players can’t afford them — WoW sells gold-cost mounts and toys priced in the hundreds of thousands of gold for exactly this reason. That’s also exactly why it’s a weak inflation control on its own: it drains currency out of the wealthiest players’ balances, but the median player was never close to that price to begin with, so their balance — and the everyday prices they experience — keeps inflating right through a report that shows this sink absorbing currency at a healthy rate. A sink only fights inflation for the players it’s actually priced to reach.
• respec and correction costs: a tax on changing your mind, which is unpopular exactly because players notice it as a sink — WoW’s talent and glyph respec fees (paid to reassign a character’s build) exist for no other reason

A second set, so the taxonomy above isn’t the only evidence#

Three more faucets and three more sinks, none of them restating the categories above: EVE Online’s incursion system pays out ISK from a shared bounty pool triggered by killing NPC fleet waves, a faucet mechanic distinct from a personal mission’s bounty; Old School RuneScape’s Thieving skill lets a trained character pickpocket coins directly from NPCs, a faucet gated by skill level rather than combat; and World of Warcraft’s looted trash items, sold individually to any vendor after a dungeon run, inject gold with no quest or bounty structure at all. On the sink side: World of Warcraft’s Auction House charges a deposit that’s forfeited if the listed item doesn’t sell, a different sink shape from a flat sales tax; character death outside a safe zone in Old School RuneScape can destroy or drop items the player then has to re-buy, a sink triggered by risk rather than a transaction; and EVE Online’s null-sec alliances pay recurring ISK upkeep just to hold sovereignty over a system, a sink with no player-facing reward attached to it at all.

The lever that matters#

A designer can’t set “the inflation rate” the way a central bank sets an interest rate — there’s no single knob. What they can do is watch the ratio of total faucet output to total sink absorption over time, in a Monthly-Economic-Report-style breakdown, and add or widen a sink when that ratio drifts. This is duller than it sounds, and it is most of the actual job.

This is also where intuition about “the” faucet needs checking against data, not guessed at. It’s tempting to assume a game’s cash-shop currency exchange — EVE’s PLEX, which converts real money into tradeable in-game value — is a side channel next to the “real” faucets like missions and bounties, since those are the ones a designer actually tunes. An independent analysis of EVE’s January 2026 Monthly Economic Report found the two are much closer than that intuition suggests: raw ISK faucets added roughly 203.6 trillion ISK that month, while players traded roughly 175.1 trillion ISK for PLEX on the open market — worth about 86% of total faucet inflow, not a rounding error next to it. PLEX itself isn’t a faucet (it’s ISK changing hands between two players, not currency created from nothing), so it doesn’t belong on the same side of the ledger as a mission payout — but a channel that size means real money is doing nearly as much work moving ISK around the economy as every mission board in the game combined, which is exactly the kind of thing “the faucet is obviously X” intuition misses without a report to check it against.

Before Week 3#

Bring one faucet and one sink from a game you actually play, described precisely enough that someone who’s never played it could identify both in a transaction log.