Furthermore, the last sliver of health shown in the UI represents more actual health points than its appearance would proportionately suggest.Īshraf (as quoted in the GDC talk) explains that these mechanics exist “to make every fight tense & interesting. However, the rate of regeneration is secretly increased when recovering the final segment of health. We know that the player’s health regenerates in combat after not taking damage for a few seconds. The first shot from offscreen is forced to miss, which gives the player a “fair” warning and an opportunity to react. A similar system exists for enemies with firearms. Given the chaos of battle, it feels subjectively unfair to be taken down suddenly from high health. The purpose of this mechanic is to provide a buffer against the negative emotion of perceived “cheap shots”. This is true even if the attack would have outright killed them.
#DONELLA MEADOWS THINKING IN SYSTEMS DIAGREAM FULL#
If the player’s health is above 66% (two full segments), then they cannot be taken below 7% health in one blow. There are two hidden systems that modulate the amount of damage taken. However, game director Ashraf Ismail revealed that the player’s health is also affected by hidden “safety belt mechanics”. This dynamic encourages the player to fight tactically, dancing in and out of combat. Unless they have recently taken damage, it will regenerate over time up to the maximum of the current segment. Their health is divided into three equal segments. For instance, consider the health system in Assassin’s Creed Origins as discussed in her talk.įrom the player’s perspective the system is fairly straightforward. Mechanics are sometimes intentionally obfuscated to create a specific aesthetic effect for the player. Jennifer Scheurle explored this topic in her 2018 GDC talk entitled “Good Game Design is like a Magic Trick”. Of course, gameplay systems are not always visible from the player’s point of view. We can use stock-and-flow diagrams as a tool to better understand the structure of these systems. Like the real world, video games are also built out of many complex systems. The rates of inflow and outflow are both affected by the current level of the temperature stock, which indicates that we have two feedback loops (both balancing). The rate of outflow is determined by the discrepancy between the indoor and outdoor temperatures. It turns the flow on/off based on the difference between the temperature in the room and the goal temperature setting. Heat flows into the room from the furnace, and the rate of inflow is determined by the thermostat. In this example, the temperature in a room is a stock. Here’s a simple real-world example as given in the book. The world is a continuum.” The boundary only exists in our mental model, and thus it must occasionally be reevaluated to suit the problem at hand. In reality, “there are no separate systems. The boundary is an intentional choice of what is considered inside and outside the system for the purpose of analysis and conversation. In stock-and-flow diagrams, feedback loops are represented by thin curved lines.Ĭlouds represent the boundary of the system. Reinforcing loops are the opposite they enhance any direction of change imposed on the system (positive feedback). Balancing loops seek to maintain equilibrium and resist change within a system (in game design this is often called negative feedback). If the rate of a flow changes based on the level of a stock, then this creates a feedback loop. The rate of a flow is represented by a faucet, because it can be adjusted higher or lower. Inflows and outflows are depicted as thick grey arrows (going to or coming from a stock, respectively). Stocks are “the elements of a system that you can see, feel, count, or measure at any given time” they are shown as boxes.įlows are what cause stocks to change over time. As the name suggests, they define systems in terms of stocks and flows. Stock-and-flow diagrams are used to model the interconnections between elements of a system. The book covers a wide range of tools and methods for systems thinking, but I’d like to focus on one technique in particular and how it could apply to game design. Having recently read Thinking in Systems: A Primer by Donella Meadows, I believe it also deserves a spot on that list. There is a certain class of books ( Understanding Comics, The Design of Everyday Things) that aren’t ostensibly about video games, but have still found their way into the informal game design canon.