Call Of Duty: 10 Huge Controversies Activision Wants You To Forget

Being name dropped by the man responsible for Norway's worst attack since WWII and associated with the deadliest mass shooting at a school in U.S history inevitably drew criticism to Activision's most played series.

Lone wolf terrorist Anders Breivik killed 77 in his attacks against the government and a Workers' Youth League summer camp in 2011, which began with a car bomb in the nation's capital Oslo, and finished with a horrifying shooting spree on the island of Utoya.

Breivik described how he "trained" for the attacks using Call of Duty: Modern Warfare, saying he practiced his aim using a "holographic aiming device" on the 2007 first-person shooter, honing his skills on the game 16 hours a day for over 12 months.

Activision's release was brought into the aftermath of another mass murder after a plumber, who worked at the home of the Sandy Hook killer, revealed the playing habits of gunman Adam Lanza.

According to the plumber, Lanza was "obsessed with the weaponry and violence in the Call of Duty franchise, spending hours on end playing the game in the family's basement. The link between the game and the horrendous actions the likes of Breivik and Lanza carried out certainly provided negative press towards Activision, and fuelled the campaigns against the violence many believe the Call of Duty series incites.