Director Uwe Boll contacted Blizzard about directing the film, but Blizzard refused. As quoted by MTV news Uwe Boll stated: "I got in contact with Paul Sams of Blizzard, and he said, 'We will not sell the movie rights, not to you... especially not to you. Because it's such a big online game success, maybe a bad movie would destroy that ongoing income, what the company has with it."
Lifesize weapons and suits of armour were built for the orcs despite the orcs being played by actors via motion capture. This was mainly for photographic references and so that they could use them as props on the set.
Bill Westenhofer, the lead visual effects supervisor for the film, is a long time World of Warcraft player and has mentioned getting up at 2 a.m. to raid with his guild while on film sets. Robert Kazinsky is also a die hard Warcraft player and recalls producers telling him to turn the game off while on the set of Pacific Rim (2013).
Duncan Jones said that the original script was very one sided; he stated it "was the stale fantasy trope of, humans are the good guys and monsters are the bad guys." After signing on to direct, he made major edits to the story, as well as the script, so both factions could tell their side of the story. He got approval from Blizzard, who was also looking to change the story.
The source for the movie adaptation is being taken from the books "Rise of the Horde," which tells how the Orcish Horde was formed; as well as "The Last Guardian," which shows the human side and reaction to Orcish invasion.