What is Machi Koro?
What am I doing?
Ever since playing this game for the first time, I realized that this is not at all a balanced game. Expecting to progress from a simple one-die early game to a two-die mid game with reasonably balanced mid-game industries, then to a late game of grabbing up Stadiums and finally the sought-after Landmark cards, I was quickly struck down from that expectation. One player bought 6 Cheese Factories in the first 6 turns, 2 Ranches, and a Train Station in the next few turns, and nothing after that. While I was busy grabbing my Mines and Business Centers, the player rolled a 7. They received 36 coins in one turn. Then they rolled a 7 again, and received another 36 coins. Without even worrying about late game industries, they simply bought all four landmark cards at their leisure. All because they owned two secondary industry cards.
So, after being inspired by a post on BoardGameGeek, I decided to run my own tests on the game. After all, user Travis Archer suggests that Cheese Factory wins nearly 75% of all 2 person games, and almost 50% of all 4 person games, making it severely overpowered. Is Cheese Factory really that powerful? Or was I unlucky in my first playthrough? I decided to run my own code to test it out.
Meet the Contenders:
I made a few deviations from Archer's Code. Most notably, I changed the buying algorithm pretty severely. Rather than purchase the most valuable card a person can purchase, my AI purchases each card in order of desirability. In other words, it needs to buy the popular cards first, otherwise it may end up dead in the water with only its now-useless secondary industries. In other other words, I have a list of things, and the AI buys each thing in the order of the list, unless the card is unavailable or if it cannot afford the card.
Each player has a value list made up of two sections; on their roll, and on other player's roll. If Player A purchases a Wheat field, they will receive 1 value at 1 their roll, and 1 other player's roll. If Player B purchases a Cafe, they will receive 1 on other player's 3 roll, and everyone else will lose 1 on their 3 roll.
Once buying could be solved, the rest of the algorithm is very straightforward. The computer rolls a dice, and doles out money depending on what values each player has on that number. We just need to simulate this about 80 times per player, until the game ends, and over the course of 10,000 games. With a running tally of who wins and when they win, we can find our Results.
Initial Results (Beating random strategies)
First of all, I had to replicate Archer's results myself. This was surprisingly easy, as it just required fixing all of the bugs in my code* and putting together a single algorithm. Playing against random strategies, the Cheese Factory performed very well. Note: As my algorithm runs a bit differently, I was able to focus my one die strategy on buying Ranches first, or buying Bakeries first. This has a non zero impact on its win rate. Although its not significant enough for me to continuously adjust it throughout the following steps.
*Exaggeration, fixing bugs is never easy.
But this is not a very realistic game state, unfortunately. This blog post is about Winning Machi Koro more consistently, not beating up some low performing strategies. If you want to beat the Fruit and Vegetable Market, for example, you can use almost anything.
Best Strategy Based on Win Time
in this plot, we can see which strategies perform best given no competition. In theory, you should always play the Bakery strategy if nobody else is buying bakeries. Ranch is a very close second. Both of them will collapse if the other players decide to purchase 3-4 Bakeries or Ranches, however.
Best Strategy based on 1v1 matchups
2 Player Results
As for Adaptability
The most concerning results of the previous sections is that there is no easy way to beat the three major strategies in a 1v1 matchup. A one die spread can sometimes outperform the Cheese Factory and Bakery strategies, but even buying two of a strategy's main card is not certainly going to stop them. You can buy more than that, but then you will eventually be playing the same strategy as they are. And if you do attempt to play the more adaptable One-Die-Spread, you can still get squashed by the Convenience Store strategy.
This is where multiple players come into play. While a One-Die-Spread is the worst of the major strategies in a 2 person game, it actually gets significantly better once the other strategies are pitted against each other. Two Cheese Factory players will make each other irrelevant. Two bakeries have the same effect. Even the Convenience store gets destroyed when its key cards are lost. The One-Die-Spread does not suffer from this problem at all. As long as you are focusing on a group of different strategies with more players, you can actually pull ahead of most.
How to Win Machi Koro
To consistently win at Machi Koro, just keep the three major strategies in mind. If you are in a two player game, just play the winning strategy against the person who starts going for another strategy. Stealing their cards doesn't usually work unless you take half of the available pile, at which point you might as well follow the same strategy.
However, with three or more players, keep your options open and go for a strategy if you can. If nobody is taking ranches, destroy them all with the Cheese Factory. If nobody is taking Bakeries, then beeline victory with the Bakery. And if nobody is taking wheat fields, do not for the love of God buy the Fruit and Vegetable market because that strategy is more of a lottery ticket than a real strategy. You can instead try the One-Die-Spread as a safe option against known strategy players.