UT^2: Winner of 2012 BotPrize in Unreal Tournament 2004 (2012)
Author: Jacob Schrum, Igor Karpov
The BotPrize competition is an annual competition to create human-like bots for the game Unreal Tournament 2004. The bots participate in free-for-all battles against other bots and human players, and try to convince the human players that they are human. Players use an in-game judging gun to tag opponents as bot or human. After five years of striving, our bot UT^2 was one of two to finally break the 50% humanness barrier and win the BotPrize in 2012. Below are some video clips from the competition, as seen though the eyes of the human judges.

This clip shows UT^2 (named Ty) dodging shots and ultimately defeating the human judge. One very challenging aspect of the competition is the need to balance skill with human-like believability. It would be trivially easy to make a nigh unstoppable kill-bot, but it is a challenge to create a bot that is competent, but still seems human.

Here UT^2 (yellow robot with game name Boyce) fires green shots from the judging gun while interacting with its opponents, just like the other human judges in BotPrize. Because humans in BotPrize have access to the judging gun, the bots also need to use the judging gun to be seen as fully human participants. This aspect of the competition makes it more challenging, because in addition to playing Unreal Tournament the way a human does, the bots also have to play the judging game.

Unreal Tournament 2004 is a very chaotic game. Multiple opponents may be present, and it isn't always clear what is going on or who is firing on who. In this clip, UT^2 (Jerrod) is distracted by one opponent while under heavy fire from another (a human judge). Amid the chaos, UT^2 manages to fight his way to a nearby weapon and obliterate his opponent.

By this point in the match the judge (Darron) has already judged our bot UT^2 (Bryce) as a human. Having been judged by Darron makes UT^2 more inclined to judge Darron back, which it does as soon as it sees Darron. The green shots being fired are from the judging gun. Because the judging gun does no damage, Darron attempts to fight UT^2 head on, even though he has just recently spawned with the weak Assault Rifle. However, once UT^2 connects with the judging gun, it switches to the Flak Cannon and makes quick work of Darron, despite his attempts to dodge.

This video shows several interactions throughout the match between a human judge (Rodrick) and our bot UT^2 (Seth). After several interactions with UT^2, Rodrick eventually judges it as human.
Igor V. Karpov Ph.D. Student ikarpov [at] gmail com
Jacob Schrum Ph.D. Alumni schrum2 [at] southwestern edu
Risto Miikkulainen Faculty risto [at] cs utexas edu
Believable Bot Navigation via Playback of Human Traces 2012
Igor V. Karpov, Jacob Schrum, Risto Miikkulainen, In Believable Bots, Philip F. Hingston (Eds.), pp. 151--170 2012. Springer Berlin Heidelberg.
Humanlike Combat Behavior via Multiobjective Neuroevolution 2012
Jacob Schrum, Igor V. Karpov and Risto Miikkulainen, In Believable Bots, Philip F. Hingston (Eds.), pp. 119--150 2012. Springer Berlin Heidelberg.
UT^2: Human-like Behavior via Neuroevolution of Combat Behavior and Replay of Human Traces 2011
Jacob Schrum, Igor V. Karpov and Risto Miikkulainen, In Proceedings of the IEEE Conference on Computational Intelligence and Games (CIG 2011), pp. 329--336, Seoul, South Korea, September 2011. IEEE.
UT^2: Winning Botprize 2012 Entry The Botprize Competition is an annual competition to program bots that appear human-l... 2012