Thomas Deer is a cultural liaison officer at the Kahnawake Language and Cultural Centre. He helped Ubisoft out on Assassin's Creed III, and did one hell of a job making sure it became easily the best representation of Native Americans in a video game.
According to this report in the Montreal Gazette, Deer "was brought on board fairly early in the process of fleshing out the game", and was responsible for overseeing the implementation of a culture often overlooked, if not presented inaccurately, in modern media.
This job meant overseeing the way Ubisoft's developers were handling the inclusion of Native American tribes in the game, but Deer says he stepped in directly on two matters, one which impacted gameplay, the other a little less direct.
The first was scalping. It was originally going to be a part of the game, a seemingly obvious one given the practice's awareness in Western culture, but once Deer says he pointed out that the Mohawk people in question didn't actually scalp (Connor/Ratonhnhaké:ton's people are Mohawk, part of the larger Iroquois confederation), it had to go.
Note: this seemingly contradicts statements made earlier in the game's development, where it was said scalping was cut because it felt "too brutal".
He also had to request a change to a cutscene, in which the developers wanted to portray Ratonhnhaké:ton's village as wearing ceremonial masks. While these masks did exist, because they're a very "private" part of their spirituality, Ubisoft took Deer's advice and left them out of the game.
Other things he helped out on included working with a Kahnawake Mohawk translator on the game's extensive native dialogue, along with helping arrange for 20-30 contemporary Mohawks to record authentic songs and sounds of children at play.
All of which seems to have paid off, as the game's reception amongst Native Americans, a demographic not usually treated with the utmost respect in games, has been positive. "It was the talk of the town - at least among younger people," says Deer. "For the first time, they actually got to play a mainstream video game that was honest about our culture, featuring a Mohawk hero they could be proud of, and gameplay in the Mohawk language. That's a phenomenal achievement.
Assassin's Creed 3's Mohawk character shaped by Kahnawake's Thomas Deer [Montreal Gazette]