Cyber-baddies mutate to win
- 09 August 2006
- From New Scientist Print Edition. Subscribe and get 4 free issues
Next time you play a video game, you may find your computer opponent has become a little more adept at finding new and interesting ways to kill you.
Steffen Priesterjahn and colleagues at the University of Paderborn in Germany have developed a way to enable video game bad guys to learn how to be even nastier.
The team used evolutionary algorithms to generate characters for the game Quake3 and then multiplied them by producing random mutations in each character's behaviour. Each of these mutants then took on the standard computer opponent. Those that performed well were "mated" to create a new selection of mutants, while the rest were discarded. The team repeated the process a number of times, finally creating characters that consistently beat the conventional computer bad guys and were much tougher for humans to play against.
For example, evolved players used tactics such as following their opponent closely while dodging from side to side. "Playing against them is quite hard because they really put the player in a defensive position," says Priesterjahn. Some characters also evolved their own defensive strategies, like running away and hiding behind pillars. Early versions had taken this tactic a little too far, refusing to come out of their hiding place and attack the opponent.
The researchers are now developing bad guys capable of stealing tactics from human players and sharing them with their computerised teammates. They also plan to evolve computer players for games other than shoot-'em-ups.