Sometimes the ratings can be a little misleading as the game may not contain anything objectionable to a broad audience, but if there are occult elements which one might find troubling then the ESRB wouldn’t really rate games for that.
When I was still in school I worked at a GameStop and I remember trying out a game one time called Metal Arms which was about a robot in a post-war setting which would use some rather frank language although it was beeped out. I couldn’t believe that the game got a rather tame rating since it was almost akin to watching an episode of South Park at points.
I remember that I would often have to plead with parents at times regarding games that they might find objectionable if they actually knew what was in them. One dad was going to let his twelve year-old son get Grand Theft Auto: San Andreas until myself and another guy had to flatout tell the guy that you beat up people for selling drugs on your turf and that the violence in the game isn’t just black-and-white good-guy-vs.-bad-guy stuff.
Kids hated me.
The “occult” stuff in the games doesn’t really bother me though. As long as the kids have a good grounding in the Faith and realize that the game is a fantasy world then they should be find so long as the game isn’t some honest indoctrination into “real” magic (or magick as “real” practitioners assert), which I don’t really think there are since no software publishing company would make a dime off of it. I intend to let my son play fantasy-themed games with wizards and the like, but offer a simple caveat to him: “Wizards aren’t real! Magic(k) is not real! That’s how the Devil really gets people with that stuff; by convincing that it’s real so that they waste their time with it and put their faith into it.” God isn’t jealous of other gods because they’re competition; he’s jealous because they’re not real.