Gold sink

Gold sink is an economic process by which a video game's ingame currency ('gold'), or any item that can be valued against it, is removed. This process is comparable to financial repression in real economies. Most commonly the genres are role-playing game or massively multiplayer online game. The term is comparable to timesink, but usually used in reference to game design and balance, commonly to reduce inflation when commodities and wealth are continually fed to players through sources such as quests, looting monsters, or minigames.

Gold sinks are commonly called drains or gold drains. They can also be associated with item drains. The intent of a sink is to remove added value from the overall economy. For example, in Ultima Online, items that were placed on the ground would be gathered by the server. This form is referred to as decay or garbage collection.

Economies in virtual worlds operate very differently from those in the real world. Passive gold sinks may be in operation at all times to slowly extract value from the game. Players are usually more willing to accept this method of sinking. Passive sinks would be item degradation, consistent taxes, or decay. Active sinks are aggressive actions by the programmers to remove excessive value. These can be changes in the severity of the passive sinks, such as higher taxes or faster decay. But more effectively, an active sink can be the selling of unique items whose intrinsic values are much lower than the selling price sold by NPC vendors. Zack Booth Simpson cites one example in Ultima Online when the NPC vendors carried blue tinted armor that couldn't be made by players. Blue armor prices could be much higher, but decayed and degraded just like any other piece of armor.

Another improvement to active sinking is to couple it to a feedback control system. Such systems can be designed to maintain a set of prices or asset ratios, and if properly set up can add a great deal of price stability to a virtual economy; one example of this can be found in the MMO MUD Alter Aeon. The feedback control system used in Alter Aeon works by tracking the total amount of money in the game in order to dynamically adjust drop rates and shop prices. Players with more than 1 million in currency are taxed for 2% of the money they own over that limit. This keeps the economy permanently stable. The peaks in the total amount of in-game currency do not vary more than 10% in a time period of 2 years.

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