With each difficulty setting, the monsters not only deal more damage, but become faster and tougher. If they're fire resistant normally, those resistances are bumped up. Their aggressiveness is also amplified, and you'll find a more varied range of powers on special monsters, as well as some that are unique to the higher difficulty settings.
Each difficulty level in Diablo III features unique armor sets as well. Each class will get more impressive-looking armor pieces as the difficulty setting is bumped up, similar to the way armor tier sets in World of Warcraft work. The artisans in the game, NPCs that set up shop in towns to provide services to you, will also have unique upgrades and distinct visual appearances once you progress beyond the initial difficulty setting.
As you may know, skill points are gone in Diablo III, and instead skills are customized through runes. When you flip the difficulty higher, you'll also come across more powerful runes that amplify the runes' basic functionality. For instance, if something were to split a projectile into five pieces, a rune from a higher difficulty will split it into more. You'll also be able to find new sets of items unique to the Inferno mode with distinct visual elements.
So what do you think? Do you see yourself playing Diablo III multiple times to snag the better rewards? Does the fact that you could potentially profit off of it with real-life dollars have an influence on you?
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