Automatic game tuning for strategic diversity

Finding the ideal game parameters is a common problem solved by game designers by manually tweaking game parameters. The aim is to ensure the desired gameplay outcomes for a specific game, a tedious process which could be alleviated through the use of Artificial Intelligence: using automatic game tuning. This paper presents an example of this process and introduces the concept of simulation based fitness evaluation focused on strategic diversity. A simple but effective Random Mutation Hill Climber algorithm is used to evolve a Zelda inspired game, by ensuring that agents using distinct heuristics are capable of achieving similar degrees of fitness. Two versions of the same game are presented to human players and their gameplay data is analyzed to identify whether they indeed find slightly more varied paths to the goal in the game evolved to be the more strategically diverse. Although the evolutionary process yields promising results, the human trials are unable to conclude a statistically significant difference between the two variants.