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One major issue with these packs is the computer lag when they load. Early in the beta it was very bad, with several seconds of lag on your end as your computer loaded in the monster graphics. If you were right where they appeared, you could be killed before you were able to move at all. This was improved in v1.08, and the lag was backloaded, so it came up after each battle, when Baal was laughing and vanishing the corpses. After v1.09 the lag was largely removed, and these days, thanks to computers in 2008 being so much more powerful than they were in 2001 when the game was new, the lag in this area isn't an issue.
Presuming that most characters will do battle right before the throne, Baal will usually unleash the next wave of SuperUniques only after the previous wave is eliminated. However, if the Sorceress lures monsters away from Baal without killing all of them and then uses [[Teleport]] to return to the throne area, Baal will spawn the next batch of monsters. For a Sorceress using Teleport, it also isn't necessary to kill all or any of these special monsters from each wave. Baal will leave after a while
, when the monsters are far enough away from the throne pursuing your character, so you can return to the throne with Teleport and can proceed to the Worldstone Chamber.[http://www.youtube.com/watch?v=YO5K8KJ-GnM&feature=PlayList&p=6EB6F356B34538C6&index=16]
After you kill all the packs Baal laughs some more, then vanishes down the portal behind his throne. You follow him down and enter a small room with the enormous Worldstone looming in the middle of the area. It's very graphically impressive. Baal is less so, and dies very quickly if there is any Static Field in the area. He doesn't attack that quickly, but does have some interesting spell effects not seen anywhere else in the game, and can even duplicate himself.