Use a group consisting of at least 20 Gunners, 15 Bombs, 50 Riflemen, and several Pyros. Having extra Riflemen or Pyros from clanmates will help. Start by placing about eight gunners in front of the Flame Towers at the bottom or top, then quickly launch all the Bombs to take out all three sets of walls protecting the base. Launch the rest of the Gunners, the Pyros, and then the Riflemen.