Quests: Act IV
The Fallen Angel
This is one of the more tragic stories in Diablo II, and you must play a bit part in it. The angel Tyrael describes one of the late champions of Pandemonium Fortress, Izual, who led an assault on Hell itself, and paid a terrible price. Izual was cast out of both Heaven and Hell, and possessed by a creature dredged up from the pits of hell for the singular purpose of torturing and imprisoning him. Tyrael feels that Izual's crimes have been fully paid for by ages or torture, and charges you with finding and releasing him. You must track down the tortured soul on the Plains of Destruction and destroy him. Once you do so you will receive two skill points to use as you see fit.

Hell's Forge
While Mephisto's Soulstone still exists, the Greater Evil still has a foothold in the mortal world. You must destroy it to lock him out of your world altogether, and doing so will require you to travel to the Hellforge and strike the Soulstone with the mighty hammer found therein. Trek across the Plains of Despair and into the City of the Damned, until you finally enter the Hellforge. There you will fight Hephasto and all his minions. Once they are defeated, equip the Hellforge Hammer and click on the Hellforge. This will destroy the Soulstone and give you a nice shower of precious jewels.

Terror's End
You knew it would eventually come to this, right? You must defeat Diablo himself in his own lair to vanquish him forever and avenge all the lives he has taken and misery he has sewn. Travel to the River of Flame and make sure to activate the nearby waypoint. Crack open the five seals in Diablo's lair to bring the Lord of Terror to you. Unfortunately, some of his cronies will show up first when you break some of the seals, so you'll have to take them out. Diablo is super tough, so taking him down is going to require some real effort and a lot of coming back from the dead. But it's worth it.

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