2009's Call of Duty: Modern Warfare II is remembered for, among other things, its controversial "No Russian" mission in which players walk alongside a terrorist and can murder innocent civilians in an airport. Designer Mohammad Alavi spoke to IGN about this mission, saying some people inside developer Infinity Ward objected to it and said it was offensive. Additionally, Alavi discussed how a military veteran was brought in to test the mission and he ended up putting the controller down and walking out.

"There were definitely some people at our company that [objected to No Russian]," Alavi said. "I thought they were overreacting, but they were 100% right. I remember one person was like, 'This is offensive. I don't want to play this level.'"

Infinity Ward co-founder Jason West made the decision to include a content warning before the mission and give players the ability to skip it entirely. Alavi didn't originally want to do this because it felt like "copping out."

"I felt that was almost being 'This is not worth you playing.' But Jason West was the one that was like, 'No. We have to have this in.' And he was right," Alavi said. "He was like, 'This is not about it being a cop out. This is about allowing people to enjoy the rest of the game, even if they don't agree with this part.'"

Also in the interview, Alavi spoke about how Activision brought in a military veteran to play Modern Warfare II, and when this person got to the No Russian level, he couldn't stomach it.

"He gets to that level and the doors open, and he instantly recognizes that they're all civilians. And he just puts the controller down and leaves the room," Alavi said. "He's like, 'I'm not playing that level.' And I was shocked. I was like, 'Wow. Okay. No. This has a strong reaction with some people.'"

The Call of Duty series celebrates its 20th anniversary this year. The next release is Call of Duty: Modern Warfare III, which launches on November 10. The game's campaign is playable beginning November 2, but only if you preorder.