An Analysis of Players and Bots Behaviors in MMORPG

"Bot", automatic robot software, has been one of most serious problems in Massively Multiplayer Online Role Playing Game (MMORPG). Bots earn much more money in a virtual world than human players, and finally collapse balance and fairness of the MMORPG. At present, many techniques have been applied to detect and exterminate bots. However, they have a common problem that the technique effective in a certain MMORPG is not equally effective in other MMORPGs, thus no general method to detect bots has been established. Toward establishing such general technique, we analyze behavioral patterns of human players and bots in server-side game log data with two commonly available features characterizing users (human players and bots): location-based information (i.e., speed of players) and action frequency information (i.e., action count per fixed time slot). The main findings of our analysis are as follows: (1) The variation of the speed of bots is smaller than that of humans (i.e, the movement of bots is more efficient). However, the discriminative power of this location-based feature is not so significant in MMORPG, while it showed good performance in First Person Shooting (FPS) game. (2) Action count and battle count indicate more discriminative power than the speed feature. In particular, the action count is more robust than battle count against the size of the time slot.