So just what was Belial's plan there?

[Lissa]

To nobody in particular, a thought occurred to me, about what's happened to the series.

D1 was clearly a classic horror. The evil you were up against were vast, ancient, and hidden. Diablo was something beyond the power of humans to defeat, the very idea of fear. Tristram is not the last refuge of epic warriors, but the charred, tragic remains of an encounter with the impossibly evil. Even at the end of your quest, once your champion had hacked and slashed your way to the end, accumulating power and equipment far beyond ordinary mortals, you merely became the monster you tried to kill. Humans = ephemeral, Evil = eternal. Angels feature in the backstory, but they are decidedly absent in any other way. Only dark cults even have any sense that the evil even exists, and their best efforts amount to little in the end. Classic Lovecraft.

D3 flips this around, weirdly. You are not infinitely less than the angels and demons - perhaps you are even slightly more. Nephalem are not heroes from Lovecraftian horror, outmatched and afraid. They're Kratos-style Godslayers, out to butcher every entity in the heavens and hells, if given any excuse at all. This is a completely different genre, something more like a comic book story, humans-as-superhumans.

I never felt, in all D3, a single moment of actual terror. I was a lot younger when I played D1, but I definitely remember fear being a major part of the emotional atmosphere of that game. (The pseudo-hardcore corpse system might have had something to do with it, in fairness, but I think atmosphere has a lot to do with it as well.)

-Jester

While I see where you're going with the comparison between the two, I think when D2 came out and the overall story wasn't really the Lovecraftian terror aspects anymore, that shifted focus for D2 and D3.

What I really have the problem with is the amount of backstory both D1 and D2 presented and the coherence of the story throughout D1 and D2 while having a convincing storyline was what really shows where D3 goes flat. D3s story isn't really convincing and at times isn't really coherent. This is because the writer, Chris Metzen, doesn't understand what truly makes a good story.

What D3 needed, in the story department, was a coherent and thought out story that didn't play like we, the audience, we're absolute idiots.