The Buster bonus round rule is one of the many rules that can be applied during the Bonus Round episodes. It can be offered on any floor for any character but is more likely upon entering floors 2 or 3. If it is offered, Buster is guaranteed to be the dungeon boss; otherwise it won't appear at all. The rule cannot appear at the same time as the Wicker Man or Warlock Bonus Round rules, since Burn? makes dice make equipment unusable for one turn instead of making dice cost health to use.

Buster

Burning dice cost 5 hp to extinguish.

When the rule activates, Burn will set dice on fire and cost 5 health instead of 2 to extinguish. If done against the Wicker Man or other enemies weak to fire, it will cost 10 health, and if done against enemies strong to fire like Buster (who will always show up with this rule active), it will cost 2 health for them to extinguish the dice.

While this makes Burn equipment much stronger throughout the dungeon (and powers up the Witch's Throw Dice ability with burned dice doing 5 fire damage), the player should also have plans to use other equipment since Buster will always show up at the end, and he'll only take half damage from fire attacks. Equipment like Leather Armor or Iron Armor can also help to reduce the burn damage.