Diablo/Archbishop Lazarus

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This is the penultimate mission of the game and you have to face it every time. At level 15, in hell, near a large pentagram drawn on the floor, you will find a staff called "Staff of Lazarus". Pick it up and take it to Cain in Tristram. He will tell you that Lazarus has probably kidnapped Albrecht and intends to sacrifice him to his dark master. He will then ask you to stop him and save the prince. When you return to the labyrinth, you will notice that a portal has appeared near the pentagram, similar to the ones you create with the Town Portal spell, but in red. It is advisable to completely clear the level of enemies before entering it. When you're done, enter the portal, and after a short cutscene, you'll be teleported to the Lair of Lazarus.

The lair may look like the first levels you played, but it's full of powerful enemies, such as Succubi and Hell Spawn. First, explore the lair, which is quite small, clearing it of any enemies you can reach. To the right and left of where you arrived, there are some enemies behind some grates, who will be targeting you with their spells. If you play as the Sorcerer or Rogue you can easily eliminate them right away, if you are a Warrior, you will probably have to wait to reach these. Then there are two tomes, near the northwest and southeast walls. Activate these tomes by standing on the circle next to them and examining them. Each of the two tomes will teleport you to one of the areas where you saw the captive enemies. If you haven't defeated them yet, now is the time to do so. The grates will also have vanished. After activating both tomes, before proceeding you should check your inventory and make sure you have a good supply of potions (if you don't have them, you can go to Tristram with Town Portal) and that you are in good health. Also make sure you have the Mana Shield spell active if you play as the Sorcerer. You are about to face a tough battle, the most difficult of the game after the final one. When you're ready, go back to where you came from and climb the circle. You will automatically be teleported to the central room, where Lazarus is.

Archbishop Lazarus will threaten you, then, when he finishes speaking, the battle will begin. This is a very challenging fight, because Lazarus has a lot of helpers, who will mainly appear in the southwest area of the room. They are mainly Hell Spawn, but besides them there are also two bosses: Red Vex and Blackjade. At the beginning you will therefore inevitably suffer damage: be ready to heal yourself whenever your vital energy drops below half. Try to take out all the secondary enemies first, ignoring Lazarus for now. If you use spells like Flame Wave or Fire Wall you may be able to eliminate all Hell Spawn in a very short time. Then focus on the two bosses. If you play as the Warrior, try to trap them in a corner to attack them easily. Rogues and Sorcerers, being able to attack from a distance, will instead have an easier time. Be careful though, because their attacks are quite powerful. Finally, after taking them out, start attacking Lazarus. Once you have eliminated all of his helpers it won't be too difficult to defeat him. However, he has the annoying ability to teleport, just like the Advocates or Zhar the Mad (of which he is a more powerful version). Again, the Stone Curse spell will be of great use to you. If you play as the Warrior, try to corner him. After defeating Lazarus, proceed to collect all the items dropped by the dead enemies in the room. You will find at least three magical items: one from Lazarus, one from Red Vex and one from Blackjade.

Then go to Tristram (use Town Portal) to restore energy and report to Cain. He will tell you that the boy you saw on the altar was not Albrecht and he will ask you to destroy Diablo. The final mission will now be unlocked. In the lair of Lazarus, you will find the red portal in the same place you arrived. Enter it to return to level 15 of the maze, near the pentagram.

REWARD: 3 magical items at random (one of wich, usually, is very powerful)