I was thinking of Drillborers Disk.

However - i now have more serious problemes! Chromaggus. The 2 first times i ran BWL i blazed right through - but the last 3 times i have tried Chromaggus have almost annoyed me to death. One of my toons will get the Chromatic Mutation debuff, and Chromaggus will get healed :-( To further the problem the one with the Mutation will not die, even after I wipe! He will just stand there until the debuff runs out - and the Chromaggus will aggro again, give him Chromatic Mutation again and it starts all over :-(

Was I just lucky the first time? How do I get past that stupid dog?