Good watch, could watch again, and can recommend. I'm not a real fan of the video game, so I think I can safely say that you don't need to know anything from the game other than it has "big monsters". The only thing I really see from the video game world is that the characters sort of "level up" as the movie progresses. I guess it sort of does world building in the same way by having "levels" or areas, but that's much more subtle. The movie uses isolation in several different ways and has some clever uses of limited resources to solve problems, but it is quite a bit of just fighting ...