Game Economy Design Guide: Sinks, Faucets & Inflation Control

What Is a Game Economy, Actually?

A game economy is any system where a resource — gold, gems, crafting materials, loot, energy, whatever a given game calls its currency — moves between the game and the player. That's it. It doesn't require an auction house, player-to-player trading, or a real-money store. A single-player roguelike where you earn gold from runs and spend it on permanent upgrades has an economy. A mobile game with three currencies, a gacha system, and a live-ops calendar has one too. The difference is complexity, not category.

This matters because a lot of teams don't realize they're running an economy until it breaks. Nobody sat down and said "we are now designing an economic system" — a designer added a gold reward here, a crafting cost there, a daily login bonus somewhere else, and the economy emerged as a side effect of a dozen unrelated decisions. That's normal. The problem isn't that the economy was never designed on purpose — it's that nobody is watching the whole system once it exists.

The Faucet/Sink Model

The clearest way to reason about any economy is the same model economists use for real ones: faucets and sinks. A faucet is anything that adds currency or resources into the system — quest rewards, daily login bonuses, loot drops, dungeon completions, achievement payouts. A sink is anything that removes them — crafting costs, repair fees, cosmetic purchases, upgrade costs, respec fees, taxes on trades.

An economy stays healthy when faucets and sinks are roughly matched over time relative to the rate new content and new players are added. It breaks down in one direction almost every time: faucets get added faster and more often than sinks, because faucets are rewarding to design (players like getting things) and sinks are the opposite (players don't enjoy losing resources, so they get deprioritized or watered down under pressure). The result is currency supply that grows faster than the things worth spending it on.

Illustrative example Imagine a game that ships with a daily login reward, three quest lines, and a weekly boss chest — four faucets — but only one meaningful sink at launch: a crafting system for a handful of gear upgrades. Six months later, the team has added two more daily reward tracks and a battle pass, all faucets, because those are the features that make a live-ops calendar look full. No new sink shipped in that window. Players are now sitting on currency with nothing left worth buying, and every new item added to the shop has to be priced absurdly high just to give the currency somewhere to go — which then makes the currency feel even less valuable, because a price tag that high signals nothing is actually attainable.

Why Economies Inflate

Inflation in a game economy works the same way it does in a real one: when the supply of currency grows faster than the supply of things worth buying with it, each unit of currency becomes worth less. The visible symptoms show up gradually. Prices on player-facing shops or crafting recipes creep upward release after release, not because the underlying items got more valuable, but because the numbers have to keep pace with a currency supply that's inflating. Rewards that used to feel exciting — a rare drop, a big quest payout — start to feel routine, because the volume of currency flowing to the average player has grown even though the item itself hasn't changed.

This is closely related to power creep, which is really the same failure mode applied to power level instead of currency: new content has to out-reward or out-perform old content to feel worth engaging with, and each cycle resets the baseline a little higher. An economy that inflates unchecked and a game that suffers from power creep are usually symptoms of the same underlying habit — adding without removing, and reviewing new content in isolation instead of against the existing system.

How to Model an Economy Before Shipping It

The single highest-leverage habit in economy design is building a simple flow model before content ships, rather than reacting to inflation after it's already visible in the data. This doesn't need to be complicated:

1. List every faucet and estimate its rate. For each source of currency, estimate how much an average player earns from it per session, per day, and per week. Include everything: quests, dailies, drops, achievements, login streaks.
2. List every sink and estimate its rate. Do the same for every place currency leaves the system — crafting, repairs, upgrades, cosmetics, respecs. Be honest about how often players actually use each sink, not how often the design intends them to.
3. Project the net flow over time. Even a basic spreadsheet — total faucets minus total sinks, projected across a few weeks or months of expected play — will surface whether the currency pool trends toward growth, stability, or drought for a typical player.
4. Segment by player type. A model built only around an "average" player misses the players who matter most for economy health: highly engaged players who play far more than average, and who will hit inflation or drought conditions long before anyone else notices.
5. Re-run the model before every content release. Every new sink or faucet shifts the balance. A recurring five-minute check against the model catches drift before it compounds into a visible problem.

This same modeling habit is what underlies good loot table design — drop rates are really just faucet rates, and a loot table tuned in isolation from the rest of the economy is a common way inflation sneaks in through the back door.

Signs an Economy Is Already Broken

A handful of player-facing symptoms reliably point back to a faucet/sink imbalance, even before anyone runs the numbers:

• Currency feels worthless. Players stop paying attention to how much of a currency they have because it no longer buys anything that feels meaningful.
• Prices keep climbing. Each new item or upgrade costs noticeably more than the last comparable one, with no corresponding jump in what it actually does.
• Players stockpile instead of spend. Large currency balances sitting unused are a sign that sinks aren't compelling enough relative to how fast currency is flowing in — the exact opposite problem from a drought, but just as unhealthy.
• New content requires ever-larger rewards to feel exciting. If every new quest or event has to out-reward the last one to register with players, that's inflation showing up as a design requirement rather than a bug report.

Quick Reference: Symptom, Cause, and First Step

A Note on Multiple Currencies

Everything above gets more complicated once a game has more than one currency — typically a free "soft" currency and a premium currency tied to real money. Each currency needs its own faucet/sink model, and the exchange rate or conversion path between them is itself a design decision with its own inflation risks. That topic is large enough to deserve its own treatment; see soft currency vs. premium currency for the framework on what each currency should and shouldn't be allowed to buy.

A Quick Self-Audit Checklist

• Every faucet and sink in the game is listed somewhere, with an estimated rate, not just implicitly understood.
• The flow model is checked against highly engaged players, not just an average player.
• New content is checked against the existing economy model before it ships, not reviewed in isolation.
• At least one new, genuinely desirable sink has shipped recently — not just a price increase on existing ones.
• Prices and rewards are anchored against a fixed reference point, not against "what the last release did."