Hi all – I’m Reko, the lead game designer at the Helsinki-based Sumea studio of Digital Chocolate. We recently released California Gold Rush for both iPhone (get it from AppStore) and Mobile and here’s some design insights into the development of the game that has already garnered some critical reviews.

What is the game about?

You are Mandy, a steadfast gal in the 1848 era California and you help Mr. Marshall to mine designated mining spots and prove they are good enough to start a proper mining operations.

Each mine has three designated goals in terms of how much money you need to make. In the mine, you can find gold veins which deposit gold nuggets in your backpack when mined. You can also find other treasures which cash in instantly.

You return to the surface and empty your backpack at the store where you can use part of that money to buy explosives, supports, maps and hear rumors about hidden mines etc.

Each movement or action you take drains your stamina and once that runs out, the level ends. If you meet any of the designated goals, you can unlock additional mines.

It’s not all about gold digging though, along the way you battle with fields of lava, ice, angry bats and less-than-expert miners who have collapsed the mine on themselves – so they need a bit of rescuing. Mandy gets her share of troubles as well as every bit of tunnel in the mines is susceptible for collapses. Collapses drain your stamina and take a chunk of money as the shopkeeper digs you out.


Original Concept and Design

The original concept was to do a game set in the 1800’s Gold Rush in California and the Sierra Nevada mountains. Why? Because of Risk vs Reward. At the start of the project, that term really solidified what the game was about. In effect, the deeper you dig, the more dangerous it would get (due to increased chance of collapsing tunnels). If you stay near the surface, it’s easier and less dangerous, but you’ll never find a huge gold vein by staying there.

The game was meant to be a slight tactical game where the player didn’t need to hurry with his decisions. We also wanted the game to land in-between the fast-paced arcade games and the faceless tycoon games. So little bit of action, little bit of thinking and a cherry on top with the buying and customization aspects.

The overall starting points of the game were:

Mine gold and turn it over for money

Use money to purchase items that help you dig deeper

Performance is based on how much money you have in the end

All this is done within a limited time per each level


Another great influence along with Risk vs Reward was the the tight decision making that goes on in boardgames with a German/eurogame flair:

Limited amount of time/turns to carry out actions

Tight decisions either through limited turns or cost of actions

Luck present, but not in a game changing fashion

Psychological aspects in the form of Greed and Exploration were also taken into account. Psychology is a big part of game design and game mechanics and is often overlooked.

Greed manifested through different size of gold veins, from tiny to huge and on to diamonds and hidden treasure chests.

Exploration was mainly on the shoulders of the fog of war system where the level is completely hidden for the player, until he digs a tunnel and starts discovering what is around him.

These two formed a good bond. The players always wanted to see what’s revealed in the fog of war, and each discovery of a gold vein grew their greed for more. Ultimately, gold allows you to beat the game and unlock real historical tidbits of the Gold Rush era.


Game Changes

The vision for the game stayed the same from the beginning, but small tweaks here and there were introduced – you can’t design games 100% on a paper, after all.

Here are some examples of areas of iteration.

Digging Gold


At first the player was meant to pick up gold nuggets from the floor, but it was too much of a burden and not really contributed much to the game. Instead, you mine gold and it goes straight in the backpack. When full, you empty it in the surface.

We played around a bit with cashing in instantly, but it broke part of the game. It’s important for the player to deliver the gold to the surface as this measures his ability to create a good tunneling system and also use supports in critical spots to prevent collapses. If you get caught in a collapse, you are returned back on top, but you lose a chunk of stamina and money.



Originally, the idea was that we’d use a real calendar and the player character has about a month in the mine to get as much gold as possible. The backstory used to be that Mr. Marshall owned these gold lands, but was about to lose them since he hadn’t started his mining operations properly. So our protagonist, Mandy, comes along and helps Marshall to get underway.

Ultimately, showing the length of the day and the amount of days left didn’t really register with the players. Even with warnings, the need to hurry never materialized.

Later on this was changed into an overall stamina where a single meter was used to describe when the level is going to end. Of course, everything from walking, digging, running away from lava and getting pestered by the bats is going to drain that stamina. It’s up to the player to decide how to use his stamina most effectively.

That’s it!

The game of California Gold Rush might start slow, but it sucks you in after a while. The palpable greed for gold, the need to see what the fog covers and the ultimate prize of finding and solving the legendary mine gives the player a tightly packed experience.

You can get California Gold Rush from your local mobile deck carrier or check out the iPhone version. Pick up the shovel and get mining!


PS. Here’s a sneak peek video of the gameplay with narration from our producer: