Brutal Legend Mission 17: Dry Ice, Wet Graves
At the start of this mission, you'll have a considerable amount of fans. Quickly spend 350 fans on upgrading your stage to Level 2. Now build up an army of Headbangers to attack one of the blocked fan geysers.
After you have captured and secured your second geyser, start upgrading your stage again to Level 3 so you can start to build Roadies to help take out Ophelia's merch booths.
As you get closer to the enemy stage your army shouldn't that far behind you. Start to weaken the foundation of Ophelia's stage by using the Bring it on Home and the Rock Block Solo.
This will not only damage the stage, but also make it harder for Ophelia to bring in reinforcements as your army begins to close in, destroying the stage, and giving you a Brutal Victoy.. This will end the mission.