Moonlight Exchange — Rules and Strategy

An investing-education game. You live 36 months (three years) in the fictional city of Moonlight, buying and selling fictional stocks. The first campaign is «Become the Stock King!».

▶ Play Moonlight Exchange · 한국어로 읽기

Language note: the game itself currently runs in Korean only. This guide exists so English readers can follow what the game is doing.

Stated up front

Every company, news item and price in this game is fictional. The game and its companion study material are general financial-education content. They are not a recommendation to buy or sell any security, and not personalised investment advice.

What the game actually teaches

It is not trying to teach you «which stocks go up». That knowledge cannot be learned in a fictional city, and should not be. What it drills instead is the habit of asking why a price moved — business cycles, interest rates, unverified rumours, diversification, fees, opportunity cost.

Core rules

1. You live 36 months. One turn is one month; after three years the campaign ends. Months remaining are opportunities remaining.
2. Eight companies. Moonlight Electronics, Lightning Games, Cloud Bank, Potato Mart, Sturdy Construction, Gold Star Mining, Starlight Bio and Moonlight Foods. Sectors react to the cycle differently — construction and games swing hard in a boom, while Potato Mart holds up comparatively well in a downturn.
3. Rumours and site visits. Rumours circulate around the city. A rumour stays live for two months before it is either confirmed or collapses. Before that resolution you can go and verify it in person.
4. You meet people. A salaryman, an heir, a shop owner, a market grandmother, an office worker, a student and an old fisherman all tell you different things. The same rumour carries different weight depending on who says it.
5. Places. Moonlight Securities, Cloud Bank, the market square, the tavern, the library. Where you go determines what you learn that month.
6. Fees and dividends. Every buy and sell costs money, and holdings can pay dividends. A dividend is not fixed interest — it shrinks or stops depending on how the company is doing.

Strategy

1. A rumour is something you verify, not something you hear

There is a reason rumours stay live for two months: to give you time to check them. Buying the instant you hear one turns straight into a loss when the rumour collapses. Verify first and your upside shrinks — but so does the size of being wrong.

2. Never investigate the same rumour twice

Because a rumour lives two months, you can go back and check it again the following month. The result is fixed, so you get the same answer. Re-investigating costs you a month, and you only ever have 36.

3. Do not write off Potato Mart as the boring stock

Learning first-hand that some companies hold their ground through a downturn is one of the things this game exists to teach. That said, it does not mean «a stock that never falls» — a defensive company is still fully exposed to accidents of its own.

4. Buying at the top of a bubble once is worth the tuition

The game records the moment you bought at the peak of a rumour and got caught in the collapse, then shows it to you on the results screen. That is not a penalty — it is the lesson. Learning it with fictional money is far cheaper.

5. Count your trades

Fees apply on both buys and sells. Costs that look trivial add up visibly over 36 months. Trading often is not the same as judging well.

6. Ask «what did I give up», not «how much did I make»

Holding cash was also a choice with an alternative. When you read your results, do not stop at the return — compare it against what else was available at the same risk. That is opportunity cost, made touchable inside a game.

Bugi's finance dictionary

There is a separate study companion that re-reads the concepts you met in the game in real-world language: business cycles, interest rates and share prices, news versus rumour, diversification, defensive stocks, safe assets, fees, price versus value, dividends, and opportunity cost — ten entries in all.

FAQ

Is it connected to real markets?

Not at all. Every company, news item and price is fictional data that exists only inside this game.

Can I continue a saved game?

Yes. Progress is saved in your browser, and rumour outcomes are fixed by rumour number and seed, so continuing or restoring a save always produces the same results.

Can I go bankrupt?

You can. That is part of the campaign too.

What age is it for?

There is no age restriction, but the content suits players old enough to ask themselves «why did this price move».

Design note — why it never tells you which stock is good

There is no «correct» company in this game. Nothing lets you know in advance what will rise, and verifying every rumour still does not produce a reliable winning formula. That is deliberate.

If you learned «what goes up» in a fictional city, that knowledge would be exactly wrong in the real world — the companies, the news and the prices exist only inside this game. A game that teaches that can be fun, but it is harmful as education: it convinces you a rule exists where none does.

What is left instead is the habit of asking. Why did this price move, where did I hear it, did I check, and how much do I lose if I am wrong. It is also why the results screen deliberately records the moment you bought at the top of a rumour and got caught in the collapse. That scene is the most valuable thing in the game.

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This page is updated whenever the rules change. If you spot an error, tell us through contact.