How ! i can destroy vault?


How can I destroy the vault, in addition to bombs ?
Oil useless with it and trebuchet !!!


I saw someone destroy a vault by throwing 10 grease orbs and then a demon fire orb. Every 10 to 15 seconds they would throw another grease orb. I was surprised how fast it destroyed the vault.

EDIT: Unless the recent patches have changed this.


But that has changed, orb useless with vault!!!