Neither of the three may have the same affix set. They do not summon any minions, but may spawn next to additional Reaper forces. Obviously, their attacks deal Fire damage instead of Cold, and their whirling attack has far greater range. There is an achievement for killing all three Maidens of Flame in a single game within 10 seconds of each other. There is a bug to achieve this easily, however: kill three illusions of one Maiden of Flame at once.