Possible Clues:

• Explosive accountant took to vault during public sacrifice
• Mass sacrifice of old
• Husband erecting splendid memorial — it's a major sacrifice
• Huge public sacrifice in combat he unleashed
• Sacrifice Tom to ravening mob
• Mob dispersed following 17's great sacrifice
• Large-scale sacrifice of old
• The sacrifice of the mass?
• Sacrifice male accountant placed on vault
• Chief witch shortly organised mob for big sacrifice