Or they could pull something completely original. Maybe Diablo isn't the final boss in the base game, but he will be in an expansion. We'll just encounter evidence of his rise to power, perhaps. Or maybe he will be the final boss, but we don't actually defeat him. Perhaps we "defeat" Diablo, he's driven out of his host somehow, and then he goes to possess someone more powerful. Is it possible for a demon to possess an angel? We could find out.
So I was thinking, what if Diablo isn't the main threat this time, I'm kind of assuming that since Aiden supposedly concieved a daughter while he was fighting for his soul (I don't get the timeline either) what if part of Diablos essence inside Leah growing and SHE becomes Diablo at the end of the game, and we have to fight him in the expansion.
Spoilers
1. Adria "comforted" the Hero/Aiden while he was lingering in Tristram between Diablo I and Diablo II. This is supposedly when they consummated.
2. That's the idea many are arguing right now, yes. That Leah contains some portion of Diablo inside herself, even though Diablo's soulstone was destroyed. So, in essence, she is acting like a soulstone, storing a "shard" of Diablo's soul. Or maybe the demonic soul fused with her own and becomes something completely new, hence the "female" model of Diablo floating around.
Spoilers
1. Adria "comforted" the Hero/Aiden while he was lingering in Tristram between Diablo I and Diablo II. This is supposedly when they consummated.
2. That's the idea many are arguing right now, yes. That Leah contains some portion of Diablo inside herself, even though Diablo's soulstone was destroyed. So, in essence, she is acting like a soulstone, storing a "shard" of Diablo's soul. Or maybe the demonic soul fused with her own and becomes something completely new, hence the "female" model of Diablo floating around.