Curing

CURING adds progress when a player cures a matching entity.

quests: # Root task configuration.
  levels: # Level entries.
    27: # Target level.
      requirements: # Requirement list.
        rules0: # Unique rule id.
          type: "CURING" # Listen for curing progress.
          entity: "ZOMBIE_VILLAGER" # Entity type being cured.
          required: "1" # Number of cures required.
        description: # Requirement descriptions.
          0: "%status%<reset> <gray>Cure 1 zombie villager</gray> <white>({currentProgress}/{maxProgress})</white>" # Description for rules0.

The bundled tasks use ZOMBIE_VILLAGER.