From Diablo Wiki
Siegebreaker is the sixth quest of Act III.
- 0 XP
Find the demon gate at the Edge of the Abyss
Kill the Siegebreaker Assault Beast
Talk to Adria near the demon gate
I come with urgent news. Leah has had another vision—a vision of twisted, demonic towers and enormous hearts beating within them!
I know of them; they are the Sin Hearts. Azmodan must have dredged them up from the depths of his realm to empower his legions.
Then let us stop these terrible hearts from beating!
Then I'll stop his hearts and his legions
Then I must destroy these hearts while I still can.
No doubt corruption flows from these hearts. I will crush them.
Then we will stop the beating of these hearts.
Then I will be happy to stop them from beating!