Anders Breivik played World of Warcraft "full-time" for a year, which the prosecution described as a violent game at his trial in a Norwegian court.
The court heard that Brevik, who is accused of killing 77 in the Norway massacre, played the game "full-time" between the summer of 2006 and the summer of 2007.
The prosecutor, who called World of Warcraft as a violent game, showed the court a picture of one of the characters Breivik adopted in the game. Breivik smiled when the image was shared.
The court was also shown an image of the bedroom where Breivik played WoW.
Breivik's character was called Justicar Andersnordic, according to the court. The name Justicar is one of the highest levels of achievement in the game, according to WoW forum user Modjo.
Breivik apparently posted in the World of Warcraft Silvermoon realm forums, according to the WoW gameplay forum.
WATCH WORLD OF WARCRAFT ABOVE.
World of Warcraft forums have been buzzing with news of his playing of the game since July 2011.
Many gamers in the forums are outraged that he took part of their hobby, some writing "I feel so dirty", "WoW should send the chat logs to Interpol ASAP.", and simply "Vile person."
Others were more circumspect. WoW player Soupyjoe wrote: "A (alleged) criminal playing a popular game?! Well, I never!" and "You know, it's likely that a very small percentage of current WoW players are criminals."
Gamers who realised they have been playing with Breivik were revolted, one wrote "the most scary thing bout his posting is that there isent a slightest bit of crazy in all of his post seemed like just a normal guy."
World of Warcraft players were reluctant to link violence in the game with Breivik's alleged actions.
WoW user Deezy wrote: "Please stop with all this "WoW is a violent video game" take in mind mass murderers always have been since day 1 till now and i don't think Gilles de Rais killed hunderds of childrens(sic) in 1400s because of WoW."
Breivik had previously admitted to using another violent video game, Modern Warfare 2, as a training tool for his alleged crime.
According to Kotaku, Breivik wrote: "I just bought Modern Warfare 2, the game, it is probably the best military simulator out there and it's one of the hottest games this year. ... I see MW2 more as a part of my training-simulation than anything else. I've still learned to love it though and especially the multiplayer part is amazing. You can more or less completely simulate actual operations."
Blizzard Entertainment, which makes World of Warcraft, was contacted for comment, which was not available at the time of publication.