Interaction with the NPC's is greatly enhanced. The menus are easy to use, and every item for sale is visually displayed. Characters run in Diablo II, and that makes gameplay faster, and more exciting. There are five character classes to choose from, each specialized in different realms of combat. Necromancers can raise the dead, and create an army of mages and zombies.
Paladins have some great auras, which enhance both defense and offense.
Auras work on the whole party, so a Paladin makes a great party addition. The Barbarian uses brute force for combat, and most of his skills center around more powerful blows, and mastering a weapon. Rounding out the five is the Sorceress. She has some wicked spells with some really great effects. Add to this three different difficulty levels, and you have a game can be played for months.