Transcript
Witchcraft: The Alchemy of a Crafting-Based Economy by Matthew Steinke Author: Armin Weiß February 20, 2017 Tags: Game, Economy, Crafting, Balancing, Merchant Track: GDC EUROPE 2015 - Programming Url: http://www.gdcvault.com/play/1022800/Witchcraft-The-Alchemy-of-a Speaker: Matthew Steinke, CD PROJEKT RED Abstract This document describes techniques that were used to create the economy and the crafting system for award winning game and how to get started designing an economy for your own one.
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Summary of Talk
How was the crafting and looting based economy for “The Witcher 3” created and balanced? What is a good approach to create an economy in your own game.
1.1
Witchcraft
Witchcraft is system of tools and guidelines that was invented in order to deal with balancing the huge economy of the game in a very limited time frame. It eliminated exploits and allowed for dynamical content generation as the player progresses through the game.
1.2
Creating of the economy
Different classes of items were listed in a spreadsheet with the lowest, average and highest value of their effectiveness. This helped to also determine the lowest, average and highest currency values for those item classes. The price progression of each item class was then charted to compare them against each other. By taking a look at the resulting chart he realized that there was an aspect he did not consider before. The prices of items increased very fast initially and very little the closer the item got to the ceiling value of attributes for that items class. This means a minor attribute increase in the early stages of the game lead to a major price increase. So he had to adjust the values of each item class in order to make it work exactly the other way around.
1.3
Dynamic economy
By using data that was attained in the initial step of design he was able to create a system that would scale the pricing of the major item classes dynamically at runtime during the game instead of trying to fit static hardcoded values into the average curve. This approach eliminated a lot of bugs and at the same time prevented the emergence of exploits. This also helped distributing the whole content of items in the different zones of the world and enabled the possibility for the loot system to always reward the players with items that they could actually use at the given point in their progress of the game.
1.4
Crafting System
Adding a crafting system to the already existing economy was a big challenge. In order to prevent exploits the sell price components that could be extracted by disassembly of items had to be adjusted in order to be around the same value of currency as the item. A new calculation system was invented. The item price was now calculated by the cost of crafting in addition to the average
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cost of attributes and the sale price scaled with left durability of the item and a new price modifier. This new price modifier was now based on which merchant the player was selling his items to, the location of the trade and the origin of the item. Books for example had reduced value on zones where people were poor ( and probably therefor unable to read ) and increased value in noble areas like the big town of Novigrad where the folk is educated.
1.5
Inventory
The Inventory in the game does not really have a limited amount of item slots but only a weight limit of what the player can carry around. With the crafting system a new problem emerged which was that players started to keep ingredients instead of using them because they might be more useful in the future. This made it really hard to balance the weight of items so he ultimately went with the decision to make ingredient’s weight almost unnoticeable.
1.6
Your own economy
He recommends to use math initially to compare curves against each other and use your instincts to tweak the solutions u came up with on a mathematical basis until it feels right to you. Instincts are vulnerable to human error though and therefor you should use playtesters to expose weaknesses in your system.
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Overview and Relevance
Economy and crafting systems are one of the most complex challenges in game development when it comes to gameplay balancing. Little changes in the economy can lead to major changes in the difficulty of a game and exploits may ruin the experience of players.
2.1
State of the Art
There are a lot of different implementations of crafting systems. Sometimes the crafting is not performed by the playable character itself, often the player has to find recipes in order to craft rare items and in some games the player has to experiment. Five crafting stereotypes, their advantages and disadvantages can be found in an article by Alexander King [?].
2.2
Big Flaws
On some games players spend more time on grinding out boring stuff than actually playing the game whereas on other games the progress is extremely slowed down due to specified time a player has to wait until he or she can gather more ingredients. Some games took flaws to a next level. Luke McKinney wrote a list of his favourite five worst flaws in video game’s crafting systems [?] which is worth to take a look on.
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References and Further Sources
[1] Leslie Lamport, LATEX: a document preparation system, Addison Wesley, Massachusetts, 2nd edition, 1994. [2] Alexander King, “5 Approaches to Crafting Systems in Games (and Where to Use Them)”, https://gamedevelopment.tutsplus.com/articles/5-approaches-to-crafting-systems-in-gamesand-where-to-use-them–cms-22628, 13 Jan 2015. [3] Luke McKinney, “The 5 Worst Flaws In Video Game Crafting Systems”, http://www.cracked.com/blog/5-ways-crafting-in-video-games-broken-and-how-to-fix-it/, 19 Sept 2015.
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