Utility and Marginal Utility

About this model

An economic concept used to describe the value in a certain decision, such as in consuming a certain good. Examples in games may include the utility in purchasing a certain item, using a certain ability, or saving gold for later. Utility is broad and sometimes hard to quantify, as it may involve complex factors such as happiness and individual preference.

This diagram represents a turn-based game scenario, focusing on a player's damage upgrade mechanics and its impact on gameplay, particularly in terms of the number of turns required to defeat an average enemy. Initially, the player deals 40 damage per turn to enemies who typically have 100 health. The diagram outlines the effect of damage upgrades on the "Turns to Kill" (TTK) an average enemy. When the player upgrades their damage, there's a calculation to determine how these upgrades reduce the number of turns needed to defeat an enemy. It notably highlights the importance of the first and sixth upgrades, which significantly reduce the TTK, showing a tangible impact on gameplay dynamics and providing immediate gratification and utility to the player.

The diagram uses sources, pools, and registers to dynamically calculate and exhibit the TTK based on the current player damage and average enemy health. Upgrading damage through interactions adds a fixed amount of damage to the player's base damage, which then alters the TTK calculation. This serves to illustrate not just the quantitative effect of each upgrade but also underscores the varying utility of different upgrades within the game's economy. The interplay between player decision-making regarding upgrades and the resulting changes in game efficiency encapsulates a critical aspect of game design: balancing immediate rewards against longer-term strategy.

This public Machinations diagram, “Utility and Marginal Utility”, was shared in the Machinations Community by Harry Ashton.

You can open the original diagram in the Machinations app, press Play to watch how resources move through it, and change its values to see how the system responds. Machinations is a visual tool for designing, simulating and balancing game economies and other systems, where resources flow through sources, pools, drains, converters and gates. In a diagram, a source creates resources, a pool stores them, a drain removes them, a converter changes one resource into another and a gate decides where they go next.