Diablo II features a lot of different quests, six in each of first three acts, and three in the fourth, and six again in the last. Quests must be completed to progress the game and find out more about the story. Quests may involve killing a particular monster, clearing an area of monsters, retrieving a specific item, or locating a certain object or place. At any rate, you are usually well rewarded for completing a quest in the form of experience and items. This section describes each of the quests, grouped by act, and gives hints on how to complete them.

Act I
This is where your journey begins. The town you are in is the Rogue Encampment. Act I in pretty much an orientation of the game, but don't let that fool you. You will be challenged with six quests. Most of the quests won't be fairly difficult, but if you don't watch it, you can be thrown head over heels. Your main goal of Act I is to defeat Andariel, as well as her evil followers. A lot of the quests are optional, and most quests are of the kill the monster type. Since this is the first act, it would be wise not to pass up any of the quests because you could use all the experience you can get.

Act II
The town of Lut Gholein is under seige both from monsters who rule the desert and from a mysterious threat from within the city itself. The City Guard is tied up defending their own palace, leaving the city streets in the hands of Griez and his mercenaries. Diablo himself has traveled to the deserts surrounding this port city in search of the tomb where his brother Baal is imprisoned within the body of a Horadarim mage. You must complete several quests to find the tomb of Tal Rasha and stop the Lord of Terror before it's too late.

Kurast was once a bright and vibrant place, but the jungle surrounding this small town has overgrown and defiled it. The people of Kurast are also caught in the middle of a violent political struggle as their leaders have fallen prey to Mehpisto, the Lord of Hatered. You must put an end to their suffering, and defeat the High Council of Zakarum. This will require the collection of several powerful (and disgusting) artifacts and, of course, lots of bloodshed.

Act IV
You track Diablo to the very shores of Hell, bent on stopping the Lord of Terror and his kindred from flooding the world with their hellish leigons and evil. You are fighting on his turf now, and all the odds are against you, your companions, and your Heavenly guide.

Act V
The Expansion provides an entirely new act to play, after you have completed the first four acts. After defeating Diablo, Tyreal appears and notify you of a siege in the Barbarian Highlands, and he opens a portal for you to travel there. The portal will take you to the town of Harrogath, where you will have to find out what's been going on to help the people.. Just like the previous acts (save for Act IV), there are six quests to complete in Act V. Ultimately, your main quest is to stop Baal from reaching the World Stone, which will let him tear down the boundary between Heaven, Hell, and Sanctuary.

The Secret Cow Level
What? The Secret Cow Level? No, this is not a joke by us but the truth. The Secret Cow Level, also known as the Moo Moo Farm, truly exists in the odd world of Diablo II. Visit this section to learn all about it.