Flow, as described by psychologist Mihaly Csikszentmihalyi, is the mental state where someone performing an activity is fully immersed in a feeling of energized focus, full involvement, and enjoyment in the activity. In essence, Flow is characterized by the complete absorption in what one does, and forgetting the rest of the world and time. Often this is referred to as “being in the zone” (Csikszentmihalyi, 2008).
Csikszentmihalyi is a psychologist with a focus on what makes people happy, and has interviewed a multitude of people regarding their state of happiness. The interviewed people that showed the highest levels of happiness ranged from rock climbers to musicians and the common denominator was that they were constantly getting small wins and getting better at what they did. They were challenging themselves and were thus growing as people and being happy in their state of Flow.
A state of Flow can be roughly translated into the state between boredom and anxiety, where you are challenged to your abilities, having clear goals and getting regular feedback on your progression. You learn and grow and keep finding new challenges to grow further.
When developing a game it’s important to figure out how long a gameplay session should be early in the process, and then design gameplay loops to fit this. Doing this helps the players feel like they can fulfill the current quest or session in time and get full satisfaction every time they play.
PC MOBA’s like League of Legends or Dota2 can be played in a session of 30-45 min and gives the full level-up experience. The session time is predictable and the player starts up the game with an expectation of being able to complete at least one full session, possibly several in a row. Of course there is still a bigger loop of leveling up your profile and smaller loops of casting spells and taking towers.
This concept of Flow can be used to design difficulty in single player games. There can be no perfect difficulty for games as that all depends on the skill- and investment-level of the player. But games can be designed so they accommodate most players, by giving the invested players something optional to do. Keeping it voluntary will make sure the casual player can skip it and still enjoy the game, while invested players can motivate themselves by creating their own difficulty – thus they all find their own Flow and can enjoy the game no matter their investment.
As the player progresses through the game, they generally expect the game/enemies to get harder to compensate for the player’s increasing skill level, the game’s progression follows a Flow Channel as well. It is expected for the player to find better “tools” to overcome the game, but the game/enemy will also get better “tools” to provide new challenges. Does this difficulty increase at a good rate? Or does it get too hard too fast, which leads to frustration, or does it get harder too slowly, leading to boredom?
From the above it can be stated that the four main elements of difficulty are player tools + skill vs enemy tools + skill. Developers can design for three of these, the outlier being player skill. The game must be able to accommodate for different skill levels or risk losing players.
Of course the game’s difficulty must be tuned along the way and at the end of production using play testers and QA, but it is vital to consider the total balance and progression from the early stages so the final tuning does not end up destroying the core of the game. The players must always have a sense of progression and purpose, they should feel like they are getting further in the game in some way.
A good way to design progression from the beginning is by having variety in the challenges the player faces. Make sure to have a rhythm between low intensity activities such as exploration and high intensity such as combat. This way the players are kept in a state of tension and release, traveling through the Flow Channel between boredom and anxiety, never having too much high or low intensity, but staying satisfied in a constant balanced rhythm. The change in activity also communicates to the player that they are progressing through the game.
As mentioned earlier, consider adding optional challenges for the invested players from the beginning as well. Be careful to design them so they feel meaningful for the player to pursue, and worth it to beat, so the optional areas are not just an afterthought.