The NPC Challenge

Gaming is transforming the world: this is not a speculation but a fact. Most of the PC and console games challenge the player to understand the game environment and act logically. These challenges arise due to uncertainty in the game behavior; new puzzles, strange monsters with special attack/defense abilities, intriguing storyline, etc. This poses a definite challenge unless the player goes through a walkthrough and makes an attempt to understand the game behavior in order to plan a defense or strategy. Of course, such attempts take away the thrill and excitement of playing a game and the real essence of gameplay and involvement will be lost. The beauty of a game lies in its ability to engage player through its flavor of suspense. After all, what is the fun of playing an action-adventure game if you know head-to-tail in the game?

           The real question is not ‘how’ game designers have articulated the game objects but rather ‘where’ player engagement is coming from. One wonders how a game object can make its own possible decisions given certain defined parameters that are bound by the game rules. This ensures that such decisions won’t be unpredictable. If they are ‘really’ predictable, can the player easily guess the next possible outcome of a Non-player Character? Leaving the guess work to the player, there may be a possibility that NPC behavior can escape some rational predictions. Does it depend on the AI programming? Of course, yes. Nevertheless a real engaging game should be in such a way that it must give a fair challenge even to the designer.

           NPC behavior is certainly limited by many factors; game genre, game rules, identification of anomalies, etc. In the designer’s perspective, the NPC must ensure that it encounters player decisions in a tactical manner to give a sense of surprise. However, this is the job of a dynamic NPC and such surprises are not new to a veteran gamer because of his ability to tackle new situations in the game environment. In addition, such NPCs are aware (I am using this word rather hesitantly) of the environment and makes complete use of space (in the game) to dodge the players attacks.

           In most of the FPS games, it is quite evident that some NPCs (especially bosses), though have their own parameters like health, ammo, etc., are aware of player’s defined parameters, but what NPCs may fail to know is the special abilities of the player; probably special powers, improved ammunition, upgrades etc. A veteran gamer tactically makes use of diverse range of equipment possessed by his character to overcome the difficulty in the game. 

            Static NPCs have predictable behavior; however, the decisions can be many. NPCs in Pacman are designed in such a way that each ghost has a unique behavior. There are five ghosts in each level: first ghost prevents the player from entering the center of the screen, the second ghost roams in the edges of the maze, the third chases the player character, the fourth one prevents the player from taking special powers, and the fifth ghost will roam randomly throughout the maze. The combination of independent NPC behavior effectively challenges the player.

            It is important to understand what intelligence is in a rational sense before analyzing the AI of NPCs. Intelligence is the ability to learn, understand and make judgments that are based on reason. However AI in games is based on intelligent ‘responses’ by NPCs in a given situation. On the contrary, player’s intelligence is boundless as long as the player is able to effectively make use of the game environment and the parameters assigned to the player character in a manner that facilitates a comprehensive understanding of a dynamic NPC behavior and act accordingly.

                                                                             Thanks for reading...

                                                                              Written by Anirudh