This doesn't meet the criteria at all
I admit it's a borderline case because the priests do have "magic powers" that could possibly be attributed to a deity. But in terms of actual game mechanics, those priests are using the same life magic that's available to every player. It appears to be a scam, but from the perspective of their-game civilization, it could be interpreted as justification for their religion.
Oh, sorry about that. I meant Dominions, not Master of Magic.
Dominions is actually a good example.
Because there are hints that there COULD actually be a real god outside these people who pretend to be one (several pretenders actually refer to other realms)... and that Pantocreator could just be real or fake as well.
Yet it is never answered. Sure... Religions are fake because they are co-opted by other beings to be their deity. Yet religion itself isn't necessarily fake.
You've gotten a bit confused here. The word is Pantokrator*, and it means, essentially,
ruler of all. For Dominions 4 and previous iterations in the series, it's basically just the previous god who ruled the world: It's just the title given to whoever wins out in the battle between pretenders and becomes the one true god, basically.
According to the message you get when you win a game, (if I'm remembering it accurately) you eventually get bored with ruling, see something interesting in space, and fly off to investigate, leaving the world up for grabs again.
* sometimes rendered in Dominions 4 as Pantocrator, but since the original word is greek (παντοκράτωρ) anyways...